Kearney got his cellphone out and dialled Tate’s number. “Knock on the door again,” he said, putting the phone to his ear. He got an old-fashioned answer machine and said, “Brian, if you’re there, pick up. I’m outside your house and I need to talk to you.” The tape ran for half a minute then stopped. “For God’s sake Brian, I can see you in there.” Kearney was dialling again when Tate opened the front door and looked out uncertainly. “It’s no good doing that,” he said. “I keep the phone somewhere else.” He was wearing some kind of heavily insulated silver parka over cargo pants and a T-shirt. A wave of heat came out of the door behind him. The hood of the parka obscured his face, but Kearney could see that it was hollow and tired-looking, in need of a shave. He looked from Kearney to Anna, then back again.

“Do you want to come in?” he said vaguely.

“Brian—” Kearney began.

“Don’t go in,” Anna said suddenly. She was still standing in the flower bed under the window.

“You don’t have to come with me,” Kearney told her.

She stared at him angrily. “Oh yes I do.”

Inside, the house was thick with heat and humidity. Tate led them into a small room at the back.

“Could you shut the door after you?” he said. “Keep the warmth in.”

Kearney looked around.

“Brian, what the fuck are you doing?”

Tate had made the room into a Faraday cage by tacking copper chicken wire to the walls and ceiling. As an extra precaution he had covered the windows with Bacofoil. Nothing electromagnetic could get into him from outside that room; nothing could get out. No one could know what he was doing, if he was doing anything. Boxes of tacks, rolls of chicken wire and Bacofoil cartons lay everywhere. The central heating was turned up full. Two standalone heaters running off bottled gas roared away in the middle of the room next to a Formica kitchen table and chair. On the table Tate had racked six G4 servers connected in parallel, a keyboard, a hooded monitor, some peripherals. He also had an electric kettle, instant coffee, plastic cups. Takeaway food cartons littered the floor. The room stank. It was immeasurably bleak and obsessive in there.

“Beth left,” Tate explained. He shivered and put his hands out to one of the heaters. His face was hard to see inside the hood of the parka. “She went back to Davis. She took the kids.”

“I’m sorry to hear that,” Kearney said.

“I bet you are,” Tate said. “I bet you are.” He raised his voice suddenly. “Look,” he said, “what do you want? I keep the phone in another room, you know? I’ve got work to do here.”