Anna picked up the fresh coffee and looked at her précis for clues. Where should she start looking? Nothing stood out. Control had been right about him: there was no-one that she could monitor for signs of contact. She clicked over into the data management system and calibrated a new set of “selectors”, filters that would be applied to internet traffic and telephony in order to trigger flags.

She started with his name, the nub of information around which everything else would be woven. She added his age — five years either way — and then the names of his parents, his aunt and uncle. She ran a search on the soldiers who shared record entries with him, applied a simple algorithm to disqualify those who only appeared once or twice, then pasted the names of the rest. She inputted credit card and bank account details, known telephone numbers and email addresses. He hadn’t had a registered address since he had left the Army, but she posted what she had and all the hotels that he had visited more than once.

His blood group, DNA profile and fingerprints had been taken when he joined the Group and, miraculously, she had those. She dragged each of them across the screen and dropped them in as new selectors.

Distinguishing marks: a tattoo on his back, a large pair of angel wings; a scar down his face, the memento of a knife fight in a Honolulu bar; a scar from the surgery to put a steel plate in his right leg after it had been crushed in a motorcycle crash.

Each piece of data and metadata narrowed the focus, disambiguating whole exabytes held on the servers in the football-pitch sized data room in the basement. She spun her web around that central fact of his name, adding and deleting strands until she had a sturdy and reliable net of information with which she could start filtering. Dozens of algorithms would analyse the data that her search pulled back, comparing it against historical patterns and returning probability matches. “John Milton” alone would generate an infinitesimally small likelihood rate, so small as to be eliminated without the need for human qualification. Adding his age might nudge the percentage up a fraction. Nationality another fraction. Adding his blood group might be worth a whole percentage point. The holy grail — a fingerprint, a DNA match — well, that happened with amateurs, but not with a man like this. That wasn’t a break she was going to catch.

She filed the selectors for approval, took another slug of coffee, applied for capacity to run a historic search of last month’s buffer — she guessed it would take a half day, even with the petaflops of processing power that could be applied to the search — and then leant back in her chair, lacing her fingers behind her head and staring at the screens.

Control was right. Milton was a ghost and finding him through a digital footprint was going to be a very long shot. GCHQ was collecting a vast haystack of data and she was looking for the tiniest, most insignificant needle. Control must have known that. If Milton was as good as he seemed to be, he would know how to stay off the grid. The only way that he would surface was if he chose to, or if he slipped up.

She stood, eyes closed, stretched out her arms and rolled her shoulders.

Anna doubted John Milton was the kind of man who was prone to mistakes.

She started to wonder if this job was a poisoned chalice.

The sort of job that could only ever make her look bad.

20

Five in the morning. Plato looked at the icon of Jesus Christ that he had fixed to the dashboard of his Dodge. Feeling a little self-conscious, he touched it and closed his eyes. Four days, he prayed. Please God, keep me safe for four days. Plato was not usually a prayerful man, but today he felt that it was worth a try. He had been unable to sleep all night, the worry running around in his mind, lurid dreams of what the cartel would do to him and his family impossible to quash. In the end, with the red digits on the clock radio by his bed showing three, he had risen quietly from bed so as not to disturb Emelia and had gone to check on each of his children. They were all sleeping peacefully. He had paused in each room, just listening to the sound of their breathing. Satisfied that they were safe, he had gone downstairs and sat in the lounge for an hour with a cup of strong black coffee. His service-issue revolver was laid on the table in front of him. It was loaded and the safety was off.

The kitchen light flicked on and Emelia’s worried face appeared at the window. Plato waved at his wife, forcing a broad smile onto his face. She knew something had happened last night but she had not pressed him on it and he had not said; he didn’t want to cause her any more anxiety than he could avoid. What was the point? She had enough on her plate without worrying about him. He might have been able to unburden himself but it would have been selfish. Far better to keep his own counsel and focus on the light at the end of the tunnel.

Four days.

He started the engine and flicked on the headlights. He backed the car down the drive, putting it into first and setting off in the direction of Avenue 16 de Septiembre and the Hospital San José. He turned off the road and rolled into the underground car park. As he reversed into a space he found himself thinking of the Englishman. It was out of character for him to break the rules, and he was quite clear about one thing: giving a man he did not know the details of where the witness in a murder enquiry was being taken was most definitely against the rules. The man wasn’t a relation and he had no obvious connection to her. He was also, very patently, a dangerous man who knew how to kill and had done so before. Plato had wondered about him during his night’s vigil. Who was he? What was he? What kind of ex-soldier. Special Forces? Or something else entirely? He had no reason to trust the man apart from a feeling in his gut that they were on the same side. Plato had long since learnt that it was wise to listen to his instincts. They often turned out to be right.

Plato rode the elevator to the sixth floor. The girl was being kept in her own room; they would be better able to guard her that way. Sanchez was outside the door. He had drawn the first watch and his eyes were red rimmed from lack of sleep.

“About time,” he grumbled.

“How is she?”

“Sleeping. The shoulder is nothing to worry about — just a flesh wound, they’ve cleaned it and tidied it up.”

“But?”

“But nothing. They shot her up to help her sleep and she’s been out ever since.”

“Has anyone told her about the others?”

“No. I didn’t have the chance.”

Plato sighed. It would fall to him to do it. He hated it, bringing the worst kind of news, but it was something that he had almost become inured to over the course of the years. How many times had he told relatives that their husband, son, wife or daughter had been murdered over the last decade? Hundreds of times. These two would just be the latest. He hoped, maybe, that they would be the last.

“Alright,” he said. “I’ll take over. Have you spoken to Alameda?”

Sanchez nodded. “He called.”

“Alright?”

“Seemed to be.”

“He’s still relieving me? I’ve got to start looking into what happened, for what it’s worth. I can’t stay here all day.”

“He said he was.”

Sanchez clapped him on the shoulder and left him.

The room was at the end of the corridor. There was a chair outside it and, on the floor, a copy of El Diario that Sanchez had found from somewhere. The front page had a number as its headline, capitalized and emboldened — SEVEN HUNDRED — and below it was a colour picture of a body laid out in the street, blood pooling around the head. It would be seven hundred and eight once they had processed the victims from last night. Plato tossed the newspaper back down onto the ground, quietly turned the handle to the door and stepped inside. The girl was sleeping peacefully. She had been dressed in hospital issue pyjamas and her right shoulder was swaddled in bandages. He stepped a little closer. She was pretty, with a delicate face and thick, black hair. The silver crucifix she wore around her neck stood out against her golden-brown skin. He wondered if it had helped her last night. She had been very, very lucky. Lucky that the cook had been there, for a start. And lucky that the sicarios had, somehow, failed to complete their orders. That was unusual. The penalty for a sicario’s failure would be his own death, often much more protracted and unpleasant than the quick and easy ending that he planned for his victims. It was a useful incentive to get the job done and it meant that they very rarely made mistakes.