The man knew he wasn’t really an individual; he was part of a hive, a single cell in a larger mind. He didn’t need to understand the whole, only his work, his duty, his small piece of the city that needed cleansing.

Tonight was special. The order was to kill again. He would follow them slowly. He would make them cry out for death. Then, he would help them.

Outside the club, his watch chimed at fifteen-minute intervals. He checked the time visually before going through his other checks. The first was his weapons check. He pulled out the small pistol, examined the magazine, removed it, took the bullet out of the breech, clicked the trigger twice, replaced the magazine, levered the bullet back into the breech. Then he took out his army combat knife, a small four-inch holed blade. He unsheathed it, felt the blade, sheathed it and put it away. Next he took out his flashlight. It was combat standard, strong and simple to use. He flicked on the beam and picked out the shadows opposite, then quickly switched it off and replaced it in his pocket. He took out the gloves. They were industrial gloves, so that he could handle the barbed wire. He was ready. He opened the window a couple of inches and pulled out a cigarette. A match flamed in the darkness; he dragged deeply and felt the rush of nicotine in his blood.

Soon, it would be time. He held the anger in and felt it spread throughout him, the rage forming in each muscle in turn, mingling with the nicotine. He didn’t just hate. Hate was for part-timers. He was hate. It was his DNA, his purpose, his sole trajectory.

Hate was a bloodline. It had grown in his cells like anything else: blue eyes, brown hair, muscularity — and hate. Hate was his inheritance, his birthright — and his duty.

He stared across, blew smoke out of the window and repeated the eighty-eight words softly to himself.

Salsa Club, Upper East Side

March 6, 11.50 p.m.

Inside the basement salsa club, the dance floor was heaving with bodies, the walls running with condensation under dark red lights. The series of small rooms reverberated with the high-pitched hoot of the trumpets and the rhythm of the bongos. A barely audible singer led the song in Spanish.

David Capske was twenty-seven, engaged to be married and very pleased with how life had changed for him. He put his arm around Lucy, pulled her in tight, sipped his fifth Corona and stared at her. She was so perfect. Lucy’s eyes followed the dancers; David, too, turned to watch.

The couple on the dance floor were breathtaking. The woman twirled in a tiny silver dress, flicking her long legs around on high heels, her elegant arms draped across the shoulders of her chisel-jawed partner. He was tall and taut in every movement — like a fixed bar against her fluidity.

The dancers moved quickly, their legs and hips lifting and falling to the rapid thump of the beat. David stared transfixed. Then he felt something on his thigh. He looked down and saw Lucy’s hand slowly moving across it.

‘You want to dance?’ he shouted over the noise.

‘I see you like to watch her dance,’ she teased. ‘You getting excited?’

David grinned. ‘I was admiring her technique. She’s got great upper-body isolation.’

‘That’s why you were staring so hard at her upper body region?’

‘What’s to look at? She’s not half as beautiful as you and she’s not even got the moves you’ve got.’ He reached out and tried to kiss her. ‘Now your upper-body isolation is second to none.’

She pulled away and smiled. ‘I need proof.’

David leaned closer. ‘That’s not a problem.’

‘How are you going to prove it to me?’

‘By taking the most beautiful woman in this place home and showing you,’ he said.

‘Flatterer! Anyway, that might be second-hand excitement. You might be thinking of anyone. I want better proof than that.’

They stared at each other. This was happiness, David Capske thought. Whatever more was to come, couldn’t compete with the feeling he had when they were together.

‘My family have disowned me, is that not proof enough?’

Lucy laughed and stood up. ‘They just want you to meet a nice Jewish girl and not some—’

‘Talented and brilliant young writer.’ He gazed into her blue eyes. He meant it. She was the one. True, Lucy Steller was not what his family had in mind for their firstborn. They were part of the wealthy establishment and she was still working in a supermarket.

‘Let’s go home then.’ She took his hands and dragged him to his feet. David kissed her.

They stood outside in the cold night air. They were both sweaty from the heat of the club, and the cold air stung. Lucy had goose bumps. David put his arm around her and rubbed her bare arm briskly to try to warm her up. The road was quiet — just a line of dark shop windows and a row of parked cars under gloomy street lights.

‘I love being with you,’ he said.

In one of the parked cars across the way, a light suddenly flared in the driver’s seat: a face illuminated for a second seemed to be staring directly across at him.

Lucy felt David’s body tense. ‘What’s up?’

‘Nothing,’ he said. The light went out in the car and smoke drifted from the half-open window. ‘Someone just lit a cigarette.’

‘We should get going,’ she said, and took his arm.

‘He was staring right at me,’ said David. ‘Not a nice look, either.’

‘Don’t start with the paranoia,’ she said, and drew him close. As they began to walk up the street, David turned and looked again over his shoulder at the parked car, but all he could see was a trail of smoke from the window.

Apartment, Lower Manhattan

March 7, 7.04 a.m.

Denise Levene lay alone in her bed, staring up at the ceiling. Everything about her had changed. She used to leave her clothes all over the room, for one, but now her whole apartment was obsessively neat; even her shoes stood in an orderly line in the closet and there wasn’t so much as a sock on the floor.

It suggested an ordered mind. And that’s how she wanted it to look.

She felt just like a dam wall trying to stop the waters from breaking through. She knew she could neither fight nor outrun the panic attacks. The best she could do was to try to distract herself. But she could feel fears looming — the black thoughts that had started to seep through from her dreams into the new day.

She held the memories at bay for several minutes. Then a half-thought appeared. His face in the shadows. And suddenly she was in the dungeon again and the whole fragile world seemed in danger of splitting open.

Denise threw back the duvet and stood up. Movement helped. She rushed through to the utility room, took her sweat-pants from the basket and pulled them on, then an old tank top. She put on a hoodie and her old sneakers and ran out of the apartment, slamming the door, heading fast down the eight flights of stairs.

Then she was out in the street gulping air. The sense of terror was intense; she felt a momentary release, but she had only avoided it for a moment — the panic was still chasing her down. She felt the thoughts hiding somewhere in her mind, just behind her eyes, waiting.

Denise sprinted up the street, avoiding the look of anonymous faces, hearing only the rumble of the city and feeling only the morning chill. Her feet pounded with long strides and her heart raced. She turned south and headed across the Brooklyn Bridge, out to the projects — the destitute parts of Brooklyn where she had grown up.

On the street her head continued to swarm with dark thoughts. The fears returned, but so did the image of Tom Harper, the man she’d once admired. She could no longer deal with him in the aftermath — and as much as he tried to contact her and talk, she just flat out refused. Tom Harper had been cut off. Daniel, her boyfriend, was another casualty. He’d stayed around long enough to know she had changed, then he took the dog and moved someplace else. Denise didn’t feel much about it.