The Palazzo Falconieri stands on a promontory on one of the smaller Italian lakes. It's late June, and a faint breeze touches the pines and cypresses that cluster like sentinels around the rocky headland. The gardens are imposing, and perhaps even beautiful, but the deep shadows lend the place a forbidding air, which is echoed by the severe lines of the Palazzo itself.

The building faces the lake, and is fronted by tall windows through which silk curtains are visible. The east wing was once a banqueting hall, but now functions as a conference room. At its centre, beneath a heavy art deco chandelier, is a long table bearing a Bugatti bronze of a panther.

At first glance the twelve men sitting around the table look ordinary enough. Successful, judging from their quietly expensive clothes. Most are in their late fifties or early sixties, with the kind of faces that you instantly forget. There is an unblinking watchfulness about these men, however, which is not ordinary.

The morning passes in discussion, which is conducted in Russian and English, the languages common to all those present. Then a light lunch -- antipasti, lake trout, chilled Vernaccia wine, fresh figs and apricots -- is served on the terrace. Afterwards the twelve men pour themselves coffee, contemplate the breeze-ruffled expanse of the lake, and pace the garden. There are no security people, because at this level of secrecy, security people themselves become a risk. Before long the men have returned to their places in the shadowed conference room. The day's agenda is simply headed "EUROPE."

The first speaker is an ageless, darkly tanned figure with deep-set eyes. He looks around him. "This morning, gentlemen, we discussed Europe's political and economic future. We talked, in particular, about the flow of capital, and how this can best be controlled. This afternoon I want to speak to you about a different economy." The room darkens, and the twelve turn to face the screen on the room's north wall showing an image of a Mediterranean port, of container ships and ship-to-shore gantry cranes.

"Palermo, gentlemen, today the principal point of entry for cocaine into Europe. The result of a strategic alliance between the Mexican drug cartels and the Sicilian Mafia."

"Aren't the Sicilians a spent force?" asks a heavyset man to his left. "I was under the impression that the mainland syndicates ran the drugs trade these days."

"That used to be the case. Until eighteen months ago the cartels dealt principally with the 'Ndrangheta, from the southern Italian region of Calabria. But in recent months a war has broken out between the Calabrians, and a resurgent Sicilian clan, the Greci."

A face appears on the screen. The dark eyes coldly watchful. The mouth a steel trap.

"Salvatore Greco has dedicated his life to resurrecting the influence of his family, which lost its place in the Cosa Nostra power structure in the 1990s, following the murder of Salvatore's father by a member of the rival Matteo family. A quarter of a century later Salvatore has hunted down and killed all of the surviving Mattei. The Greci, and their associates the Messini, are the richest, most powerful, and most feared of the Sicilian clans. Salvatore is known to have personally murdered at least sixty people, and to have ordered the deaths of hundreds more. Today, at fifty-five years of age, his hold over Palermo and its drug trade is absolute. His enterprises, worldwide, turn over some twenty to thirty billion dollars. Gentlemen, he's practically one of us."

A faint ripple of amusement, or something approximating to it, runs around the room.

"The problem with Salvatore Greco is not his predilection for torture and murder," he continues. "When mafiosi kill mafiosi it's like a self-cleaning oven. But recently he has started ordering the assassination of members of the establishment. To date, his tally is two judges and four senior magistrates, all killed by car bombs, and an investigative journalist, who was gunned down last month outside her apartment. The journalist was pregnant at the time of her death. The child did not survive."

He pauses, and raises his glance to the screen with the image of the dead woman, spreadeagled on the pavement in a pool of blood.

"Needless to say, it has not been possible to directly implicate Greco in any of these crimes. Police have been bribed or threatened, witnesses intimidated. The code of silence, or omertà, prevails. The man is, to all intents and purposes, untouchable. A month ago I sent an intermediary to arrange a meeting with him, as I felt that we needed to reach some sort of accommodation. His activities in this corner of Europe have become so excessive that they threaten to impact on our own interests. Greco's response was immediate. The following day I received a sealed package." The image on the screen changes. "It contained, as you can see, my associate's eyes, ears and tongue. The message was clear. No meeting. No discussion. No accommodation."

The men around the table regard the grisly tableau for a moment, then return their gaze to the speaker.

"Gentlemen, I think we need to take an executive decision concerning Salvatore Greco. He is a dangerously uncontrollable force, and beyond the reach of the law. His criminal activities, and the social havoc they entail, threaten the stability of the Mediterranean sector. I propose that we remove him from the game, permanently."

Rising from his chair, the speaker makes his way to a side-table, returning with an antique lacquered box. Taking out a black velvet drawstring bag, he pours its contents on the table in front of him. Twenty-four small ivory fish, twelve of them aged to a smooth yellow, twelve of them stained a dark blood-red. Each man receives a contrasting pair of fish.

The velvet bag makes its way around the table counter-clockwise. When it has made a full revolution, it is passed to the man who proposed the vote. Once again, the contents of the bag are poured onto the dimly gleaming surface of the table. Twelve red fish. A unanimous sentence of death.

It's evening, a fortnight later, and Villanelle is sitting at an outside table at Le Jasmin, a private members club in Paris's Sixteenth Arrondissement. From the east comes the murmur of traffic on the Boulevard Suchet, to the west is the Bois de Boulogne and the Auteuil racecourse. The club's garden is bordered by a trellis hung with blossoming jasmine whose scent infuses the warm air. Most of the other tables are occupied, but conversation is muted. The light fades, the night awaits.

Villanelle takes a long sip of her Grey Goose vodka Martini, and discreetly surveys the surroundings, particularly noting the couple at the next table. Both are in their mid-twenties: he elegantly dishevelled, she cat-like and exquisite. Are they brother and sister? Professional colleagues? Lovers?

Definitely not brother and sister, Villanelle decides. There's a tension between them -- a complicity -- that's anything but familial. They're certainly rich, though. Her silk sweater, for example, its dark gold matching her eyes. Not new, but definitely Chanel. And they're drinking vintage Taittinger, which doesn't come cheap at Le Jasmin.

Catching Villanelle's eye, the man raises his champagne flute a centimetre or two. He murmurs to his companion, who fixes her with a cool, assessing stare.

"Would you like to join us?" she asks. It's a challenge, as much as an invitation.

Villanelle stares back, unblinking. A breeze shivers the scented air.

"It's not compulsory," says the man, his wry smile at odds with the calm of his gaze.

Villanelle stands, lifts her glass. "I'd love to join you. I was expecting a friend, but she must have been held up."

"In that case…" The man rises to his feet. "I'm Olivier. And this is Nica."

"Villanelle."

The conversation unfolds conventionally enough. Olivier, she learns, has recently launched a career as an art dealer. Nica intermittently works as an actress. They are not related, nor on closer inspection do they give the impression of being lovers. Even so, there is something subtly erotic in their complicity, and the way they've drawn her into their orbit.

"I'm a day-trader," Villanelle tells them. "Currencies, interest-rate futures, all that." With satisfaction, she notes the immediate dimming of interest in their eyes. She can, if necessary, talk for hours about day-trading, but they don't want to know. Instead, Villanelle describes the sunlit first-floor flat in Versailles from which she works. It doesn't exist, but she can picture it down to the ironwork scrolls on the balcony and the faded Persian rug on the floor. Her cover story is perfect now, and deception, as always, affords her a rush of pleasure.

"We love your name, and your eyes, and your hair, and most of all we love your shoes," says Nica.

Villanelle laughs, and flexes her feet in her strappy satin Louboutins. Catching Olivier's eye, she deliberately mirrors his languid posture. She imagines his hands moving knowledgeably and possessively over her. He would see her, she guesses, as a beautiful, collectible object. He would think himself in control.

"What's funny?" asks Nica, tilting her head and lighting a cigarette.

"You are," says Villanelle. How would it be, she wonders, to lose herself in that golden gaze? To feel that smoky mouth on hers. She's enjoying herself now; she knows that both Olivier and Nica want her. They think that they're playing her, and Villanelle will go on letting them think so. It will be amusing to manipulate them, to see how far they will go.

"I have a suggestion," says Olivier, and at that moment the phone in Villanelle's bag begins to blink. A one-word text: DEFLECT. She stands, her expression blank. She glances at Nica and Olivier, but in her mind they no longer exist. She's out of there without a word, and in less than a minute is swinging into a northbound stream of traffic on her Vespa.

It's three years now since she first met the man who sent her the text. The man who, to this day, she knows only as Konstantin. Her circumstances, then, were very different. Her name was Oxana Vorontsova, and she was officially registered as a student of French and Linguistics at the University of Perm, in central Russia. In six months' time she was due to sit her finals. It was unlikely, however, that she would ever walk into the university's examination hall as, since the previous autumn, she'd been unavoidably detained elsewhere. Specifically, in the Dobryanka women's remand centre in the Ural Mountains. Accused of murder.

It's a short drive, perhaps five minutes, from Le Jasmin to Villanelle's apartment near the Porte de Passy. The 1930s building is large, anonymous and quiet, with a well-secured underground garage. After parking the Vespa alongside her car, a fast and anonymous silver-grey Audi TT Roadster, Villanelle takes the lift to the sixth floor, and ascends the short flight of stairs to her rooftop apartment. The front door, although faced with the same panelling as the others in the building, is of reinforced steel, and the electronic locking system is custom-made.

Inside, the apartment is comfortable and spacious, even a little shabby. Konstantin handed Villanelle the keys and title deeds a year ago. She has no idea who lived there before her, but the place was fully furnished when she moved in, and from the decades-old fixtures and fittings, she guesses it was someone elderly. Uninterested in decoration, she has left the apartment as she found it, with its faded sea-green and French-blue rooms, and its nondescript post-Impressionist paintings.

No one ever visits her here -- her professional meetings take place in cafes and public parks, her sexual liaisons are mostly conducted in hotels -- but if they were to do so, the apartment would bear out her cover story in every detail. In the study, her computer, a top-of-the-range wafer of stainless steel, is protected by civilian security software that a halfway skilled hacker would quickly bypass. But a scan of its contents would reveal little more than the details of a successful day-trading account, and the contents of the filing cabinet are similarly non-committal. There is no music system. Music, for Villanelle, is at best a pointless irritation and at worst a lethal danger. In silence lies safety.

Conditions at the remand centre were unspeakable. The food was barely edible, the sanitation non-existent, and an icy, numbing wind from the Dobryanka river penetrated every cheerless corner of the institution. The slightest infraction of the rules resulted in a prolonged period of shiza, or solitary confinement. Oxana had been there for three months when she was ordered from her cell, marched without explanation to the prison courtyard, and ordered to climb into a battered all-terrain vehicle. Two hours later, deep in the Perm Krai, the driver halted by a bridge over the frozen Chusovaya river, and wordlessly directed her to a low, prefabricated unit, beside which a black four-wheel- drive Mercedes was parked. Inside the unit, there was just enough room for a table, two chairs, and a paraffin heater.

A man in a heavy grey coat was sitting on one of the chairs, and to begin with, he just looked at her. Took in the threadbare prison uniform, the gaunt features, the posture of sullen defiance. "Oxana Borisovna Vorontsova," he said eventually, consulting a printed folder on the table. "Age, twenty-three years and four months. Accused of triple homicide, with multiple aggravating circumstances."

She waited, staring out of the window at a small square of snowy forest. The man was ordinary enough looking, but she knew at a glance that this was not someone who could be manipulated.

"In a fortnight's time you will face trial," he continued. "And you will be found guilty. There is no other conceivable outcome, and in theory you could be sentenced to death. At best you will spend the next twenty years of your life in a penal colony which will make Dobryanka look like a holiday resort."

Her eyes remained blank. The man lit a cigarette, an imported brand, and offered her one. It would have bought her an extra helping of food for a week at the remand centre, but Oxana refused it with a barely perceptible shake of the head.

"Three men found dead. One with his throat slashed to the bone, two shot in the face. Not quite the behaviour expected of a final year linguistics student at Perm's top university. Unless, perhaps, she happened to be the daughter of a Spetsnaz close-quarter battle instructor." He drew on his cigarette. "Quite a reputation he had, Senior Sergeant Boris Vorontsov. Didn't help him, though, when he fell out with the gangsters he was moonlighting for. A bullet in the back, and left to die in the street like a dog. Hardly a fitting end for a decorated veteran of Grozny and Pervomayskoye."

From beneath the table he took a flask and two cardboard cups. Poured slowly, so that the scent of strong tea infused the cold air. Nudged one of the cups towards her.

"The Brothers' Circle. One of the most violent and ruthless criminal organisations in Russia." He shook his head. "What were you thinking, exactly, when you decided to execute three of their foot soldiers?"

She looked away, her expression disdainful.

"It's just as well the police found you before the Brothers did, or I wouldn't be talking to you now." He dropped his cigarette end on the floor and trod it out. "But I have to admit it was an efficient piece of work. Your father taught you well."

She glanced at him again. Dark-haired, medium height, perhaps forty years old. His gaze was level and his eyes were almost, but not quite, sympathetic.

"But you neglected the most important rule of all. You got caught."

She took an exploratory sip of her tea. Reached across the table, took one of the cigarettes, and lit it. "So who are you?"

"Someone before whom you can speak freely, Oxana Borisovna. But first, please confirm the truth of the following." He took a folded sheaf of papers from his coat pocket. "Your mother, who was Ukrainian, died when you were seven, of thyroid cancer, almost certainly as a consequence of her exposure to radiation following the Chernobyl reactor disaster twelve years earlier. Three months after your mother's death your father was posted to Chechnya, at which point you were taken into the temporary care of the Sakharov orphanage in Perm. You spent eighteen months at the orphanage, during which time the staff noted your exceptional academic skills. They also identified other traits, including habitual bed-wetting and a near-total inability to form relationships with other children."

She exhaled, the smoke a long grey plume in the cold air, and touched the tip of her tongue to a ridge of scar tissue on her upper lip. The gesture, like the scar itself, was barely perceptible, but the man in the coat saw it, and noted it.

"When you were ten your father was seconded again, this time to Dagestan. You returned to the Sakharov orphanage where, after three months, you were discovered setting fire to the dormitory block, and transferred to the psychiatric unit of Municipal Hospital Number 4 in Perm. Against the advice of your therapist, who had diagnosed you as suffering from a sociopathic personality disorder, you were returned home to your father. The following year you commenced your studies at Industrialny District secondary school. Here, once again, you won praise for your academic results -- particularly for your language skills -- and once again it was noted that you made no attempt to make friends or form relationships. Indeed, it's on the record that you were involved in, and suspected of instigating, a number of violent incidents.

"You did, however, form an attachment to your French teacher, a Miss Leonova, and became extremely agitated when you learned that she had been subjected to a serious sexual assault while waiting for a bus late at night. Her supposed assailant was arrested but later released for lack of evidence. Six weeks later he was discovered in woodland near the Mulyanka river, incoherent with shock and blood loss. He had been castrated with a knife. Doctors succeeded in saving his life but his attacker was never identified. At the time of these events you were approaching your seventeenth birthday."

She trod out her cigarette on the floor. "Is this leading anywhere?"

He almost smiled. "I could mention the gold medal you won for pistol shooting at the University Games in Ekaterinburg. In your first year as an undergraduate."

She shrugged, and he leaned forward in his chair. "Just between ourselves. Those three men in the Pony Club, what did you feel when you killed them?"

She met his gaze, her expression blank.

"OK, hypothetically. What might you have felt?"

"At the time, I might have felt satisfaction at a job well done. Now…" She shrugged again. "Nothing."

"So for nothing, you are looking at twenty years in Berezniki, or somewhere similar?"

"You brought me all the way here to tell me that?"

"The truth, Oxana Borisovna, is that the world has a problem with people like you. Men or women who are born, as you were, without a conscience, or the ability to feel guilt. You represent a tiny fraction of the population at large, but without you…" He lit another cigarette, and sat back in his chair. "Without predators, people who can think the unthinkable, and act without fear or hesitation, the world stands still. You are an evolutionary necessity."

There was a long silence. His words confirmed what she had always known, even at her lowest ebb: that she was different, that she was special, that she was born to soar. She stared through the window at the waiting vehicle, and the guards stamping their feet in the snow. Again, the tip of her tongue momentarily probed her upper lip.

"So what do you want from me?" she asked.

Konstantin told her, sparing no detail of what was to come. And listening to him, it was as if everything in her life had led to that moment. Her expression never flickered, but the thrill that ripped through her was as avid as hunger.

Over Paris, the light is fading. From a drawer in the desk in her study, Villanelle takes a new, boxed Apple laptop, and unpacks it. Soon she is connected to a Gmail account and is opening a message whose subject heading is Jeff and Sarah -- Holiday Pics. There are two paragraphs of text, and a dozen JPEG images of a couple exploring tourist sites in and around Cairo.

Hi All!

We've had the best time ever. Pyramids amazing, and Sarah rode a camel (see attached pics)! Back on Sunday, landing 7.42, should be home by 9.45. Best wishes -- Jeff.

PS please note Sarah's new email SMPrice88307@gmail. com

Ignoring the letters and words Villanelle extracts the figures. These make up a one-time password, which enables her to access the compressed data embedded in the innocent-looking JPEG images. She remembers the words of the Indian systems designer who taught her covert communication: "Encrypted messages are all very well, but even if they're completely unbreakable, they attract attention. Much better to ensure that no one suspects the existence of the message in the first place."

She turns to the photographs. Because they're highly detailed, with excellent resolution, they can carry a substantial data payload. Ten minutes later she has extracted all of the concealed text, which she combines into a single document.

A second email headed Steve's mobile has a briefer message, just a single phone number, and six JPEG images of an amateur football game. Villanelle repeats the earlier process, but this time extracts a series of photographic portraits. They are all of the same man. His eyes are dark, almost black, and the set of his mouth is hard. Villanelle stares at the pictures. She has never seen the man before, but there's something in his face that she recognises. A kind of emptiness. It takes her a moment to remember where she's seen that look before. In the mirror. In her own eyes. The text document is headed Salvatore Greco.

One of the unique attributes that recommended Villanelle to her present employers was her photographic memory. It takes her thirty minutes to read the Greco file, and when she has finished she can recall every page as if she were holding it in front of her. Culled from police files, surveillance logs, court records, and informers' statements, it is an exhaustive personal portrait. All things considered, though, it is frustratingly brief. A timeline of Greco's career to date. An FBI psychological profile. A breakdown, in large part hypothetical, of his domestic situation, personal habits and sexual proclivities. A list of properties held in his name. An analysis of his known security arrangements.

The portrait that emerges is of a man of austere tastes. Pathologically averse to public attention, he is extremely skilled at avoiding it, even in an era of mass communication. At the same time his power stems in large part from his reputation. In a region of the world where torture and murder are routine, Greco's ferocity sets him apart. Anyone who dares to stand in his way or question his authority is eliminated, usually with spectacular cruelty. Rivals have seen their entire families shot, informers discovered with their throats slashed and their tongues drawn out through the gaping wounds.

Villanelle looks out over the city. To the left, the Eiffel Tower is silhouetted against the evening sky. To the right is the dark mass of the Tour Montparnasse. She considers Greco. Sets his personal refinement against the baroque horror of his actions and commissions. Is there any way she can turn this contradiction to her advantage?

She re-reads the document file, scanning each sentence for a possible entrée. Greco's principal residence, a farmhouse in a hill-village outside Palermo, is a fortress. His family lives there, protected by a loyal and vigilant team of armed bodyguards. His wife, Calogera, rarely leaves home; his only daughter, Valentina, lives in a neighbouring village, where she is married to the oldest son of her father's consigliere. The region has its own dialect and a history of obdurate hostility to outsiders. Those whom Greco wishes to meet -- allied clan members, prospective associates, his tailor, his barber -- are invited to the farmhouse, where they are searched, and if necessary disarmed. When Greco leaves home to visit his mistress in Palermo, he is invariably accompanied by an armed driver and at least two bodyguards. There appears to be no predictable pattern to these visits.

One document in particular, though, interests Villanelle. It's a five-year-old press cutting from the Italian newspaper Corriere della Sera reporting a near-fatal accident sustained by one of the paper's own journalists in Rome. According to Bruno De Santis: "I was coming out of a restaurant in Trastevere when a car came racing towards me on the wrong side of the street. The next thing I knew, I was in hospital, lucky to be alive."

De Santis's none-too-subtle suggestion is that this attempt on his life is the consequence of a piece he wrote for the Corriere a month earlier, about a young Sicilian soprano named Franca Farfaglia. In the piece, he criticised Farfaglia for having accepted a donation towards her studies at the La Scala Theatre Academy in Milan from Salvatore Greco, "the notorious organised crime boss."

It is a brave and perhaps foolhardy piece of journalism, but Villanelle is not interested in De Santis. Instead, she wonders what inspired Greco's generosity towards Farfaglia -- not that he couldn't afford an infinity of such gestures. Was it a love of opera, the wish to help a talented local girl to achieve her potential, or an altogether more basic desire?

An Internet search produces a wealth of images of Farfaglia. Commanding in appearance, with proud, severe features, she looks older than her twenty-six years. Several of the images reappear on the singer's own website, where there's a history of her career to date, a selection of performance reviews, and her schedule for the next few months. Scrolling through the engagements, Villanelle pauses. Her eyes narrow, and she touches a fingertip to the scar on her lip. Then, clicking on the hyperlink, she brings up the website of the Teatro Massimo in Palermo.

Oxana's training took the best part of a year.

The worst came first. Six weeks of fitness training and unarmed combat on a lonely, wind-scoured stretch of the Essex coast. She arrived in early December. The instructor was a former Special Boat Service instructor named Frank, a knotty, taciturn figure of about sixty, with a gaze as cold as the North Sea. His habitual get-up, worn in all weathers, was a faded cotton tracksuit and a pair of old tennis shoes. Frank was merciless. Oxana was underweight and in poor condition following her months in the Dobryanka remand centre, and for the first fortnight the interminable runs across the marshes, with the sleet whipping at her face and the greasy coastal mud sucking at her boots, were torture.

Determination kept her going. Anything, even death from exposure on the mudflats, was better than returning to the Russian penal system. Frank didn't know who she was, and didn't care. His brief was simply to bring her to combat readiness. For the duration of the course she lived in an unheated Nissen hut on a mud-and-shingle island linked to the mainland by a quarter-mile-long causeway. During the Cold War, the place had been an early warning station, and something of its grim, apocalyptic purpose lingered.

On the first night Oxana was so cold she couldn't sleep, but from then on exhaustion took its toll, and she was wrapped in her single blanket and dead to the world by 9 p. m. Frank kicked the corrugated-iron door open every morning at 4 a. m. before tossing her the day's rations -- usually a plastic canteen of water and a couple of tins of processed meat and vegetables -- and leaving her to pull on her T-shirt, combat trousers and boots, invariably still sodden from the day before. For two hours they ran repeated circuits of the island, either across the oozing grey mudflats or along the icy tideline, before returning to the Nissen hut to brew tea and heat up a mess-tin of rations on a small hexamine stove. By sunrise, they would be outside again, pounding the mudflats until Oxana was vomiting with fatigue.

In the afternoons, as the darkness closed in, they worked on hand-to-hand combat. Over the years Frank had taken elements of ju-jitsu, street-fighting and other techniques and refined them into a single discipline. The emphasis was on improvisation and speed, and practice sessions were often conducted knee-deep in the sea, with the mud and shingle shifting treacherously beneath their feet. Realising that her English was poor, Frank taught by physical example. Oxana thought she knew a thing or two about fighting, having learnt the basics of the Systema Spetsnaz from her father, but Frank seemed to anticipate every move she attempted, deflecting her blows with casual ease before pitching her, yet again, into the icy seawater.

Oxana didn't think she'd ever hated anyone as much as she hated the ex-SBS instructor. No one, even in the Perm orphanage or the Dobryanka remand unit, had so systematically belittled and humiliated her. Hatred became a simmering rage. She was Oxana Borisovna Vorontsova, and she lived by rules that few would even begin to understand. She would beat this angliski ublyodok, this donkey-fucker, if it killed her.

Late one afternoon in the final week they were circling each other in the incoming tide. Frank had a Gerber knife with an eight-inch blade, Oxana was unarmed. Frank moved first, swinging the oxidised blade so close to her face that she felt the breeze of its passing, and in response she ducked under his knife-arm and hammered a short-arm punch into his ribs. It stopped him for a second, and by the time the Gerber came slicing back she was out of reach. They danced back and forth, and Frank lunged for her chest. Her body outraced her brain. Half-turning she grabbed his wrist, wrenched him in the direction to which he was already committed, and booted his legs from under him. As Frank fell backwards into the water, arms flailing, she was already lifting her knee to stamp his knife-hand into the shingle --"Control the weapon, then the man" her father had always told her -- and as the instructor involuntarily released the Gerber, fell forwards to pin him underwater. Straddling him, she forced his head back with the palm of her hand, and watched the agonised working of his face as he began to drown.

It was interesting -- fascinating, even -- but she wanted him alive to acknowledge her triumph, so she dragged him onto the shore, where he rolled onto his side and retched up gouts of seawater. When he finally opened his eyes, she was holding the point of the Gerber knife to his throat. Meeting her eyes, he nodded in submission.

A week later, Konstantin came to collect her, looking her up and down with quiet approval as she waited, rucksack slung loosely over one shoulder, on the muddy track leading to the causeway. "You look good," he said, his flat gaze taking in her newly confident stance and windburned, salt-blistered features.

"You know she's a fucking psycho," said Frank.

"Nobody's perfect," said Konstantin.

Two days later Oxana flew to Germany for three weeks' escape and evasion training at the mountain warfare school in Mittenwald. She was attached to a NATO Special Forces cadre, and her cover story was that she was on secondment from a Russian Interior Ministry counter-terrorism unit. On the second night, while dug into deep snow, she felt stealthy fingers at the zip of her bivvy bag. A silent but furious fight erupted in the darkness, and the following day two of the NATO soldiers were helicoptered off the mountain, one with a severed forearm tendon, the other with a stab wound through the palm of his hand. After that, no one bothered her.

Immediately after Mittenwald, she was flown to a U. S. Army facility in Fort Bragg, North Carolina, where she was put through an advanced Resistance to Interrogation programme. This was calculatedly nightmarish, and designed to induce maximal stress and anxiety in its subjects. Shortly after her arrival Oxana was stripped naked by her male guards and marched to a brightly lit, windowless cell, empty except for a close-circuit camera mounted high on one wall. Time passed, hour after endless hour, but she was given only water, and without toilet facilities was forced to use the floor. Before long the cell stank, and her stomach was twisting with hunger. If she tried to sleep, the cell would reverberate with white noise, or with electronic voices repeating meaningless phrases at ear-splitting volume.

At the end of the second day -- or it might have been the third -- she was hooded, and led to another part of the building where she was questioned, in fluent Russian and for hours on end, by unseen interrogators. Between these sessions, in which she was offered food in exchange for information, she was forced to adopt agonising and humiliating stress positions. Starved, sleep-deprived and severely disoriented, she drifted into a trance-like state, in which the boundaries between her senses blurred. She managed, nevertheless, to hang on to some vestigial sense of self, and to the knowledge that the experience would come to an end. However terrifying and degrading it turned out to be, it was preferable to life in the secure wing of a Ural Mountains penal colony. By the time the exercise was officially pronounced over, Oxana was beginning, in a deeply perverse way, to enjoy it.

Further courses followed. A month of weapons familiarisation at a camp to the south of Kiev, in Ukraine, followed by three more at a Russian sniper school. This was not the high-profile establishment outside Moscow where the Spetsnaz Alfa and Vympel detachments trained, but a much more remote facility near Ekaterinburg, run by a private security company whose instructors asked no questions. Being back in Russia felt strange to Oxana, even under the false identity provided by Konstantin. Ekaterinburg, after all, was less than two hundred miles from where she had grown up.

It wasn't long, though, before the deception began to give her a certain heady satisfaction. "Officially, Oxana Vorontsova no longer exists," Konstantin informed her. "A certificate issued at Perm Regional Clinical Hospital indicates that she hanged herself in her cell at the Dobryanka remand centre. District records show that she was buried at public expense in the Industrialny cemetery. Trust me, no one misses her, and no one is looking for her."

Severka urban sniper school was built around a deserted town. In Soviet times it had been home to a thriving community of scientists studying the effects of radiation exposure; now it was a ghost town, peopled only by life-sized target dummies, strategically situated behind plate-glass windows and at the wheels of rusting, skeletal vehicles. It was an eerie place, silent except for the wind that whistled between its empty buildings.

Oxana's basic training was with the standard-issue Dragunov. Soon, though, she graduated to the VSS, or Special Sniper Rifle. With its exceptionally light weight and integral silencer, it was the ideal urban weapon. By the time she left Severka she had fired thousands of rounds under a variety of operational conditions, and in less than a minute was able to arrive at a firing point with the VSS in its polystyrene case, assemble the weapon, zero the sights, calculate windspeed and other vectors, and squeeze off a lethal head or body-shot ("one shot, one kill," in the words of her instructor) at a range of up to four hundred metres.

Oxana sensed herself changing, and the results pleased her. Her observational ability, sensory skills and reactive speeds had all been extraordinarily enhanced. Psychologically, she felt invulnerable, but then she had always known that she was different from those around her. She felt none of the things they felt. Where others would experience pain or horror, she knew only a frozen dispassion. She had learned to imitate the emotional responses of others -- their fears, their uncertainties, their desperate need for affection -- but she had never fully experienced them. She knew, however, that if she was to escape notice in the world it was essential to wear a mask of normality, and to disguise the extent of her difference.

She had learnt, very young, that people could be manipulated. Sex was useful in this regard, and Oxana acquired a voracious appetite. Not so much for the act itself, although this had its satisfactions, as for the thrill of pursuit and psychic domination. For lovers, she liked to choose authority figures. Her conquests had included schoolteachers of both genders, a Spetsnaz colleague of her father's, a young woman from a military academy in Kazan against whom she was competing in the University Games, and most satisfying of all, the psychotherapist she'd been referred to for assessment in her first year at university. Oxana had never felt the slightest need to be liked, but it gave her profound satisfaction to be desired. To see the look in her conquest's eyes -- that final melting of resistance -- which told her the transfer of power was complete.

Not that it was ever quite enough. Because for all its fierce excitement, that moment of submission invariably marked the end of Oxana's interest. The story was always the same, even with Yuliana, the psychotherapist. By yielding to Oxana, by surrendering her mystery, she made herself undesirable. And Oxana simply moved on, leaving the older woman bereft, her personal and professional self-esteem in tatters.

After the sniper course, she learnt about explosives and toxicology in Volgograd, surveillance in Berlin, advanced driving and lock-picking in London, and identity management, communications and coding in Paris. For Oxana, who had never left Russia before her appointment with Konstantin at the Chusovaya Bridge, the international travelling was dizzying. Each course was taught in the language of the country in question, testing her linguistic aptitude to the limit and, more often than not, leaving her mentally as well as physically drained.

Throughout it all, patient and imperturbable on the sidelines, was Konstantin. He maintained a professional distance between himself and Oxana, but was sympathetic towards her on the handful of occasions when the pressure became too much, and she demanded, coldly, to be left alone. "Take a day off," he told her on one occasion in London. "Go and explore the city. And start thinking about your cover name. Oxana Vorontsova's dead."

By November, her training was almost over. She had been staying in a dingy one-star hotel in the Paris suburb of Belleville, and travelling every day to an anonymous office building in La Défense, where a young man of Indian origin was teaching her the finer points of steganography -- the science of concealing secret information in computer files. On the final day of the course Konstantin appeared, paid her hotel bill, and accompanied her to an apartment on the Quai Voltaire, on the Left Bank.

The first-floor apartment was furnished with spare, minimal chic. Its occupant was a tiny, fierce-looking woman of about sixty, dressed completely in black, whom Konstantin introduced as Fantine.

Fantine stared at Oxana, appeared unimpressed by what she saw, and asked her to walk around the room. Self-conscious in her faded T-shirt, jeans and trainers, Oxana complied. Fantine watched her for a moment, turned to Konstantin, and shrugged.

And so began the final stage of Oxana's transformation. She moved into a four-star hotel two streets away, and each morning joined Fantine for breakfast in the first-floor apartment. At nine o'clock every morning a car came for them. On the first day they went to the Galeries Lafayette on Boulevard Haussmann. Fantine marched Oxana round the department store, ordering her to try on a succession of outfits -- daywear, casual, evening -- and buying them whether Oxana liked them or not. The tight, flashy clothes to which Oxana was drawn Fantine dismissed without a glance.

"I'm trying to teach you Parisian style, chérie, not how to dress like a Moscow streetwalker, which you obviously know how to do already."

By the end of the day, the car was piled high with shopping bags, and Oxana was beginning to enjoy the company of her ruthlessly critical mentor. Over the week that followed they visited shoe shops and fashion houses, couture and prêt-à-porter shows, a vintage emporium in St. Germain, and the costume and design museum at the Palais Galliera. At each of these, Fantine offered an unsparing commentary. This was chic, clever and elegant; that was crass, tasteless and irredeemably vulgar. One afternoon Fantine took Oxana to a hairdresser in the Place des Victoires. Her instructions to the stylist were to proceed as she chose, and to ignore anything that Oxana suggested. Afterwards, Fantine stood her in front of a mirror, and Oxana ran a hand through her short, blunt-cut hair. She liked the look that Fantine had put together for her. The designer biker jacket, the stripy T-shirt, the low-rise jeans and ankle boots. She looked… Parisian.

Later that afternoon, they visited a boutique selling scent on the rue du Faubourg Saint-Honoré. "Choose," said Fantine. "But choose well." For ten minutes Oxana stalked the elegant shop floor, before stopping in front of a glass display cabinet. The assistant watched her for a moment. "Vous permettez, Mademoiselle?" he murmured, handing her a slender glass phial with a scarlet ribbon at its neck. Cautiously, Oxana touched the amber scent to her wrist. Fresh as a spring dawn, but with darker base notes, it spoke to something deep inside her.

"It's called Villanelle," said the assistant. "It was the favourite scent of the Comtesse du Barry. The perfume house added the red ribbon after she was guillotined in 1793."

"I shall have to be careful, then," said Oxana.

Two days later, Konstantin came to collect her from the hotel. "My cover name," she said. "I've chosen it."

As she crosses the Piazza Verdi in Palermo, her heels clicking faintly on the cobblestones, Villanelle glances up at the imposing frontage of Sicily's, and indeed Italy's, largest opera house. Palm trees rise from the piazza, their leaves whispering faintly in the warm breeze; bronze lions flank the broad entrance stairway. Villanelle is wearing a silk Valentino dress and elbow-length Fratelli Orsini opera gloves. The dress is red, but so darkly shaded as to be almost black. A spacious Fendi shoulder bag hangs by a slim chain. Villanelle's face is pale in the evening light, and her hair is pinned up with a long, curved clip. She looks glamorous, if less showy than the socialites in Versace and Dolce & Gabbana thronging the mirrored entrance hall. First nights at the Teatro Massimo are always an occasion, and tonight's offering is Puccini's Tosca, one of the most popular operas of all. That the title role is being sung by a local soprano, Franca Farfaglia, makes the occasion unmissable.

Villanelle buys a programme and moves through the entrance hall to the vestibule. The place is filling fast. There's a buzz of conversation, the muted clink of glasses and an aroma of expensive scent. Ornate wall-lights paint the marble decorations with a soft lemon glow. At the bar she orders a mineral water, and notices that she is being watched by a lean, dark-haired figure.

"Can I get you something more… interesting?" he asks, as she pays for her drink. "A glass of champagne perhaps?"

She smiles. He is thirty-five, she guesses, give or take a year or two. Saturnine good looks. His silver-grey shirt is impeccable and his lightweight blazer looks like Brioni. But his Italian has the rasp of Sicily, and there's an edge of threat in his gaze.

"I won't," she says. "Thank you."

"Let me guess. You're obviously not Italian, even though you speak the language. French?"

"Sort of. It's complicated."

"So do you like Puccini operas?"

"Of course," she murmurs. "Although La Bohème is my favourite."

"That's because you're French." He holds out his hand. "Leoluca Messina."

"Sylviane Morel."

"So what brings you to Palermo, Mademoiselle Morel?"

She is tempted to terminate the conversation. To walk away. But he might follow, which would make things worse. "I'm staying with friends."

"Who?"

"No one you'd know, I'm afraid."

"You'd be surprised who I know. And trust me, everyone here knows me."

Half turning, Villanelle allows a sudden smile to light her face. She waves towards the entrance. "Will you excuse me, Signor Messina. My friends are here." That was less than convincing, she reproves herself as she edges through the crowd. But there's something about Leoluca Messina -- some long acquaintanceship with violence -- that makes her want him to forget her face.

Will Greco come, Villanelle wonders, moving through the crowd with vague purpose, scanning the faces around her as she goes. According to Konstantin's local contact, who has had several of the front-of-house staff discreetly bribed and questioned, the Mafia boss comes to most of the important first nights. He always arrives at the last moment and takes the same box, which he occupies alone, with bodyguards stationed outside. Whether he has actually booked to come tonight has, frustratingly, been impossible to establish. But his protégée Farfaglia is singing the lead soprano role. The odds are good.

At considerable cost, Konstantin's people have secured the neighbouring box to the one Greco favours. It is on the first tier, almost directly adjacent to the stage. With ten minutes to curtain-up, and with the box on her left as yet unoccupied, Villanelle enters the nest of red plush. The box is at once public and private. At the front, perched on one of the gilt chairs, with the scarlet-upholstered rail at chest level, Villanelle can see and be seen by everyone in the auditorium. If she leans forward past the partition, she can look into the front of the boxes on either side of her. With the house lights extinguished, however, each box will become a secret world, its interior invisible.

In the gloom of that unseen, secret world, she slips her bag from her shoulder and takes out a lightweight Ruger automatic pistol with an integrated Gemtech suppressor and inserts a clip of.22mm low-velocity rounds. Returning the weapon to the bag, she places it on the floor at the base of the partition separating her from the box to her left.

In the nine months following her rebirth as Villanelle, she killed two men. Each project was initiated by a one-word text from Konstantin, followed by the transmission of detailed background documents -- film clips, biographies, surveillance reports, schedules -- from sources unknown to her. Each planning period lasted about four weeks, in the course of which she was armed, informed of any logistical support she might expect, and provided with an appropriate identity.

The first target, Yiorgos Vlachos, had been buying radioactive cobalt-60 in Eastern Europe with a probable view to detonating a dirty bomb in Athens. She had put an SP-5 round through his chest as he changed cars in the port of Piraeus. The shot, taken with a Russian VSS at a range of 325 metres, had involved an all-night lie-up under a tarpaulin on a warehouse roof. Later, reliving the event in the safety of her hotel room, Villanelle felt an intense, heart-pounding exhilaration. The dry snap of the suppressed report, the distant smack of the impact, the collapsing figure in the scope.

The second target was Dragan Horvat, a Balkan politician who ran a human trafficking network. His mistake had been to take his work home with him, in the form of a pretty, heroin-addicted seventeen-year-old from Tblisi. Unaccountably, he had fallen in love with her, and taken to flying her on expensive shopping sprees in European capital cities. London was the couple's favourite weekend destination, and when Villanelle bumped into him in a Bayswater side street late one evening Horvat smiled indulgently. He didn't immediately feel the stab wound to the inner thigh that severed his femoral artery, and as he bled to death on the pavement his Georgian girlfriend watched him with spaced-out eyes, absently twisting the gold bracelet that he'd bought her that afternoon in Knightsbridge.

In between kills Villanelle lived in the Paris apartment. She explored the city, sampled the pleasures it had to offer, and enjoyed a succession of lovers. These affairs always took the same course: a heady pursuit, a devouring couple of days and nights, the abrupt termination of all contact. She simply vanished from their lives, as swiftly and as mystifyingly as she had entered them.

She ran in the Bois de Boulogne every morning, attended a ju-jitsu dojo in Montparnasse, and practised her marksmanship at an elite shooting club in Saint-Cloud. Meanwhile, unseen hands paid her rent and managed her trading activities, whose proceeds were paid into a current account at the Société Générale. "Spend what you like," Konstantin told her. "But stay under the radar. Live comfortably but not excessively. Don't leave a trail."

And she didn't. She made no surface ripple. Became part of that monochrome army of professionals who hurried from place to place, their solitude stamped into their gazes. What authority imposed the sentences of death that she executed, she didn't know. She didn't ask Konstantin, because she was certain that he wouldn't tell her, and in truth, she didn't really care. What mattered to Villanelle was that she had been chosen. Chosen as the instrument of an all-powerful organisation which had understood, just as she herself had always understood, that she was different. They had recognised her talent, sought her out, and taken her from the lowest place in the world to the highest, where she belonged. A predator, an instrument of evolution, one of that elite to whom no moral law applied. Inside her, this knowledge bloomed like a great dark rose, filling every cavity of her being.

Slowly, the auditorium of the Teatro Massimo begins to fill. Sitting back in her seat, Villanelle studies the programme, her face shadowed by the partition between her box and the next. The performance time arrives and the house lights dim, the audience hubbub fading to silence. As the conductor takes his bow, to warm applause, Villanelle hears a figure quietly take his place in the adjoining box. She doesn't turn, and as the curtain rises on the first act, leans forward to gaze with rapt attention at the stage.

Minute succeeds minute; time is slowed to a crawl. Puccini's music engulfs Villanelle, but does not touch her. Her consciousness is focused, in its entirety, on the unseen person to her left. She forces herself not to look, but senses his presence like a pulse, malign and infinitely dangerous. At moments, she feels a coldness at the nape of her neck, and knows that he is watching her. Finally the strains of the Te Deum die away, the first act ends, and the crimson and gold curtain falls.

As the house lights come up for the interval, and conversation swells in the auditorium, Villanelle sits motionless as if hypnotised by the opera. Then, without a sideways glance, she stands and leaves the box, noting with her peripheral vision the presence of two bodyguards who are lounging, bored but watchful, at the end of the corridor.

Moving unhurriedly into the vestibule, she makes her way to the bar and orders a glass of mineral water, which she holds but doesn't drink. At the far end of the room, she sees Leoluca Messina moving towards her. Pretending she hasn't seen him, she turns into the crowd, re-emerging near the entrance to the foyer. Outside, on the opera house steps, the heat of the day has not yet abated. The sky is rose-pink over the sea, a livid purple overhead. Half-a-dozen young men passing Villanelle whistle and make appreciative comments in the local dialect.

She returns and takes her place in her box moments before the curtain rises on the second act. Once again she makes a point of not glancing to her left at Greco; instead, she gazes fixedly at the stage as the opera unfolds. The story is a dramatic one. Tosca, a singer, is in love with the painter Cavaradossi, who has been falsely accused of aiding the escape of a political prisoner. Arrested by Scarpia, the chief of police, Cavaradossi is condemned to die. Scarpia, however, proposes a deal: if Tosca gives herself to him, Cavaradossi will be released. Tosca agrees, but when Scarpia approaches her, she seizes a knife and kills him.

The curtain falls. And this time, when Villanelle has finished applauding, she turns to Greco and smiles, as if seeing him for the first time. It is not long before there is a knock at the door of the box. It is one of the bodyguards, a heavyset man who enquires, not discourteously, if she would care to join Don Salvatore for a glass of wine. Villanelle hesitates for a moment and then politely nods her acceptance. As she steps into the corridor the second bodyguard looks her up and down. She has left her bag in the box, her hands are empty, and the Valentino dress clings to her lean, athletic form. The two men glance knowingly at each other. It is clear that they have delivered many women to their boss. The heavyset man gestures to the door of Greco's box. "Per favore, Signorina…"

He stands as she enters. A man of medium height in an expensively cut linen suit. A lethal stillness about him, and a smile that doesn't begin to reach his eyes. "Excuse my presumption," he says. "But I couldn't help observing your appreciation of the performance. As a fellow opera lover I was wondering if I might offer you a glass of frappato? It comes from one of my vineyards, so I can vouch for its quality."

She thanks him. Takes an exploratory sip of the cold wine. Introduces herself as Sylviane Morel.

"And I am Salvatore Greco." There is a questioning note in his voice but her gaze does not flicker. It is clear to him that she has no idea who he is. She compliments him on the wine and tells him that it is her first visit to the Teatro Massimo.

"So what do you think of Farfaglia?"

"Superb. A fine actress and a great soprano."

"I'm glad you like her. I was fortunate enough to assist, in a small way, with her training."

"How wonderful to see your belief in her confirmed."

"Il bacio di Tosca."

"Excuse me?"

"Questo è il bacio di Tosca. 'This is Tosca's kiss!' Her words when she stabs Scarpia."

"Of course! I'm sorry, my Italian…"

"Is most accomplished, Signorina Morel." Again, that icy half-smile.

She inclines her head in denial. "I don't think so, Signor Greco." Part of her is conducting the conversation, part of her is calculating ways and means, timing, evasion routes, exfiltration. She is face to face with her target, but she is alone. And this, as Konstantin has so often made clear, is how it will always be. No one else can be involved except in the most peripheral, disconnected way. There can be no backup, no staged diversion, no official help. If she's taken, it's the end. There will be no discreet official leading her from the cell, no waiting vehicle to speed her to the airport.

They talk. For Villanelle, language is fluid. Most of the time she thinks in French, but every so often she awakes and knows that she's been dreaming in Russian. At times, close to sleep, the blood roars in her ears, an unstoppable tide shot through with polyglot screams. On such occasions, alone in the Paris apartment, she anaesthetises herself with hours of web-surfing, usually in English. And now, she notes, she is mentally playing out scenarios in Sicilian-inflected Italian. She hasn't sought out the language, but her head echoes with it. Is there any part of her that is still Oxana Vorontsova? Does she still exist, that little girl who lay night after night in urine-sodden sheets at the orphanage, planning her revenge? Or was there only ever Villanelle, evolution's chosen instrument?

Greco wants her, she can tell. And the more she plays the well-born, impressionable young Parisienne with the wide-eyed gaze, the greater his desire grows. He's like a crocodile, watching from the shallows as a gazelle inches closer to the water's edge. How does it usually play out? she wonders. Dinner somewhere they know him well, with the waiters deferential and the bodyguards lounging at a neighbouring table, followed by a chauffeured drive to some discreet, old town apartment?

"Every first night, this box is reserved for me," he tells her. "The Greci were aristocrats in Palermo before the time of the Habsburgs."

"In that case I consider myself fortunate to be here."

"Will you stay for the final act?"

"With pleasure," she murmurs, as the orchestra strikes up.

As the opera continues, Villanelle once again gazes raptly at the stage, waiting for the moment that she has planned. This comes with the great love duet, "Amaro sol per te." As the final note dies away, the audience roars its applause, with cries of "Bravi!" and "Brava Franca!" echoing from every corner of the house. Villanelle applauds with the others, and eyes shining, turns to Greco. His eyes meet hers, and as if on impulse, he seizes her hand and kisses it. She holds his gaze for a moment, and raising her other hand to her hair, unfastens the long, curved clip, so that the dark tresses fall to her shoulders. And then her arm descends, a pale blur, and her clip is buried deep in his left eye.

His face blanks with shock and pain. Villanelle presses the tiny plunger, injecting a lethal dose of veterinary-strength etorphine into the frontal lobe of his brain and inducing immediate paralysis. She lowers him to the floor, and glances around. Her own box is empty, and in the box beyond, an elderly couple are dimly visible, peering at the stage through opera glasses. All eyes are on Farfaglia and the tenor singing Cavaradossi, both standing motionless as wave after wave of applause breaks over them. Reaching over the partition, Villanelle recovers her bag, retires into the shadows, and takes out the Ruger. The double snap of the suppressed weapon is unremarkable, and the low-velocity.22 rounds leave barely a loose thread as they punch though Greco's linen jacket.

The applause is subsiding as Villanelle opens the door of the box, her weapon concealed behind her back, and beckons concernedly to the bodyguards, who enter and genuflect beside their employer. She fires twice, less than a second separating the silenced shots, and both men drop to the carpeted floor. Blood jets briefly from the entry wounds in the back of their necks, but the men are already dead, their brainstems shot through. For several long seconds, Villanelle is overwhelmed by the intensity of the killings, and by a satisfaction so piercing that it's close to pain. It's the feeling that sex always promises but never quite delivers, and for a moment she clutches herself, gasping, through the Valentino dress. Then slipping the Ruger into her bag and squaring her shoulders, she exits the box.

"Don't tell me you're leaving, Signorina Morel?"

Her heart slams in her chest. Walking towards her down the narrow corridor, with the sinister grace of a panther, is Leoluca Messina.

"Unfortunately, yes."

"That's too bad. But how do you know my uncle?"

She stares at him.

"Don Salvatore. You've just come out of his box."

"We met earlier. And now, if you'll excuse me, Signor Messina…"

He looks at Villanelle for a moment, then steps firmly past her and opens the door of Greco's box. When he comes out, a moment later, he is carrying a gun. A Beretta Storm 9mm, part of her registers as she levels the Ruger at his head.

For a moment they stand there unmoving, then he nods, his eyes narrowing, and lowers the Beretta. "Put that away," he orders.

She doesn't move. Aligns the fibre-optic foresight with the base of his nose. Prepares to sever a third Sicilian brainstem.

"Look, I'm glad the bastard's dead, OK? And any minute now, the curtain's going to come down and this whole place is going to be crowded with people. If you want to get out of here, put that gun away and follow me."

Some instinct tells her to obey. They hurry through the doors at the end of the corridor, down a short flight of stairs, and into a crimson-upholstered passageway encircling the stalls. "Take my hand," he orders, and Villanelle does so. Coming towards them is a uniformed usher. Messina greets him cheerily, and the usher grins. "Making a quick getaway, Signor?"

"Something like that."

At the end of the passageway, directly below Greco's box, is a door faced in the same crimson brocade as the walls. Opening it, Messina pulls Villanelle into a small vestibule. He parts a blanket-like curtain and suddenly they are backstage, in the heavy half-dark of the wings, with the music, relayed by tannoy from the orchestra pit, blaring about them. Men and women in nineteenth-century costume swim out of the shadows; stagehands move with regimented purpose. Placing an arm round Villanelle's shoulder, Messina hurries her past racks of costumes and tables set with props, then directs her into the narrow space between the cyclorama and the brick back wall. As they cross the stage they hear a volley of musket-fire. Cavaradossi's execution.

Then more corridors, discoloured walls hung with fire extinguishers and instructions for emergency evacuation of the house, and finally they are stepping from the stage door onto the Piazza Verdi, with the sound of traffic in their ears and the livid purple sky overhead. Fifty metres away, a silver and black MV Agusta motorcycle is standing at a bollard on the Via Volturno. Villanelle climbs up behind Messina, and with a low growl of exhaust they glide into the night.

It's several minutes before they hear the first police sirens. Leoluca is heading eastwards, winding through side streets, the MV Agusta nervily responsive to the sharp twists and turns. At intervals, to her left, Villanelle catches a glimpse of the lights of the port and the inky shimmer of the sea. People glance at them as they pass -- the man with the wolfish features, the woman in the scarlet dress -- but this is Palermo; no one looks too closely. The streets narrow, with washing suspended above and the sounds and smells of family meals issuing through open windows. And then a dark square, a derelict cinema and the baroque facade of a church.

Rocking the bike onto its stand, Messina leads her down an alley beside the church, and unlocks a gate. They are in a walled cemetery, a city of the dead, with family tombs and mausoleums extending in dim rows into the night. "This is where they'll bury Salvatore when they've dug your bullets out of him," says Messina. "And sooner or later, where they'll bury me."

"You said you were happy to see him dead."

"You've saved me the trouble of killing him myself. He was un animale. Out of control."

"You'll take his place?"

Messina shrugs. "Someone will."

"Business as usual?"

"Something like that. But you? Who do you work for?"

"Does it matter?"

"It matters if you're going to come after me next." He draws the squat little Beretta from his shoulder holster. "Perhaps I should kill you now."

"You're welcome to try," she says, drawing the Ruger.

They stare at each other for a moment. Then, without lowering the weapon, she steps towards him, and reaches for his belt. "Truce?"

The sex is brief and savage. She holds the Ruger throughout. Afterwards, placing her gun hand on his shoulder for balance, she wipes herself with the tail of his shirt.

"And now?" he says, watching her with awed repulsion, and noting how, in the half-light, the asymmetrical tilt of her upper lip makes her look not sensual, as he'd previously imagined, but coldly rapacious.

"Now you go."

"Will I see you again?"

"Pray that you don't."

He glances at her for a moment and walks away. The MV Agusta kicks into life with a snarl and fades into the night. Picking her way downhill between the tombs, Villanelle finds a small clearing in front of a pillared mausoleum. From the Fendi shoulder bag she takes a Briquet lighter, a crumpled blue cotton frock, a pair of wafer-thin sandals and a lingerie-fabric money belt. The money belt holds 500 in cash, an airline ticket, and a passport and credit card identifying her as Irina Skoryk, a French national born in Ukraine.

Quickly changing her clothes, Villanelle makes a pyre of the Valentino dress, all documents relating to Sylviane Morel, and the green contact lenses and brunette wig that she has been wearing. The fire burns briefly but intensely, and when there is nothing left she sweeps the ashes into the undergrowth with a cypress branch.

Continuing downhill, Villanelle finds a rusty exit gate, and a path leading down steps to a narrow lane. This gives onto a broader, busier road, which she follows westwards towards the city centre. After twenty minutes she finds what she has been looking for: a large wheeled garbage bin behind a restaurant, overflowing with kitchen waste. Pulling on the opera gloves she looks around her, and makes sure that she's unobserved. Then she plunges both hands into the bin, and pulls out half a dozen bags. Unknotting one, she thrusts the Fendi shoulder bag and the Ruger into the stinking mess of clam shells, fish heads and coffee grounds. Returning the bag to the bin, she piles the others on top. Last to disappear are the gloves. The whole operation has taken less than thirty seconds. Unhurriedly, she continues walking westwards.

At 11 a. m. the following morning, agent Paolo Vella of the Polizia di Stato is standing at the bar of a cafe in the Piazza Olivella, taking coffee with a colleague. It has been a long morning; since dawn Vella has been manning the cordon at the main entrance to the Teatro Massimo, now a crime scene. The crowds, by and large, have been respectful, keeping their distance. Nothing has been officially announced, but all Palermo seems to know that Don Salvatore Greco has been assassinated. Theories abound, but the general assumption is that this is family business. There's a rumour that the hit was carried out by a woman. But there are always rumours.

"Will you look at that," breathes Vella, all thoughts of the Greco murder temporarily banished. His colleague follows his gaze out of the cafe into the busy street, where a young woman in a blue sundress -- a tourist, evidently -- has paused to watch the sudden ascent of a flight of pigeons. Her lips are parted, her grey eyes shine, the morning light illuminates her close-cropped hair.

"Madonna or whore?" asks Vella's colleague.

"Madonna, without question."

"In that case, Paolo, too good for you."

He smiles. For a moment, in the sun-dazed street, time stands still. Then as the pigeons circle the square, the young woman continues on her way, long limbs swinging, and is lost in the throng.