Nigel and Daisy ran along radiating corridors, opening doors.

Kit's eye was caught by two stick figures, male and female, on a door: the toilets. He ran across the hall. There was a short corridor leading to separate men's and ladies' rooms. Kit went into the men's room.

It appeared empty. "Mr. Tremlett?" He pushed open all the cubicle doors. No one was there.

As he stepped out, he saw Steve returning to the reception desk. The guard must have been in the ladies' room-searching for Susan, Kit realized.

Steve turned around, hearing Kit. "Looking for me?"

"Yes." Kit realized he could not apprehend Steve without help. Kit was younger, and athletic, but Steve was a fit man in his thirties, and might not give up without a fight. "Something I need to ask you," Kit said, playing for time. He made his accent more Scots than was natural, ro make sure Steve did not find his voice familiar.

Steve lifted the flap and entered the oval of the desk. "And what would that be?"

"Just a minute." Kit turned away and shouted after Nigel and Daisy. "Hey! Back in here!"

Steve looked troubled. "What's going on? You lot aren't supposed to be wandering around the building."

"I'll explain in a minute."

Steve looked hard at him and frowned. "Have you been here before?"

Kit swallowed. "No, never."

"There's something familiar about you."

Kit's mouth went dry and he found it hard to speak. "I work with the emergency team." Where were the others?

"I dont like this." Steve picked up the phone on the desk.

Where were Nigel and Daisy? Kit shouted again: "Get back in here, you two!"

Steve dialed, and the mobile in Kit's pocket rang. Steve heard it. He frowned, thinking, then a look of shocked understanding came over his face. "You messed with the phones!"

Kit said, "Stay calm, and you won't get hurt." As soon as the words were out of his mouth, he realized his mistake: he had confirmed Steve's suspicions.

Steve acted quickly. He leaped nimbly over the desk and ran for the door.

Kit yelled: "Stop!"

Steve stumbled, fell, and got up again.

Daisy came running into the hall, saw Steve, and turned toward the main door, heading him off.

Steve saw that he could not make it to the door and turned instead into the corridor leading to BSL4.

Daisy and Kit ran after him.

Steve sprinted down the long corridor. There was an exit toward the rear of the building, Kit recalled. If Steve made it outside, they might never catch him.

Daisy was well ahead of Kit, arms pumping like a sprinter, and Kit recalled her powerful shoulders in the swimming pool; but Steve was running like a hare, and pulling away from them. He was going to escape.

Then, as Steve drew level with the door leading to the control room, Elton stepped into the corridor in front of him. Steve was going too fast to take evasive action. Elton stuck out a foot and tripped Steve, who went flying.

As Steve hit the ground, face down, Elton fell on him, with both knees in the small of his back, and pushed the barrel of a pistol into his cheek. "Don't move, and you won't get shot in the face," he said. His voice was calm but convincing.

Steve lay still.

Elton stood, keeping the gun pointed at Steve. "That's the way to do it," he said to Daisy. "No blood."

She looked scornful.

Nigel came running up. "What happened?"

"Never mind!" Kit shouted. "We're out of time!"

"What about the two guards in the gatehouse?" Nigel said.

"Forget them! They don't know what's happened here, and they're not likely to find out-they stay out there all night." He pointed at Elton. "Get my laptop from the equipment room and wait for us in the van." He turned to Daisy. "Bring Steve, tie him up in BSL4, then get into the van. We have to go into the laboratory-now!"

12:45 AM

IN the barn, Sophie had produced a bottle of vodka.

Craig's mother had ordered lights out at midnight, but she had not come back to check, so the youngsters were sitting in front of the television set, watching an old horror movie. Craig's dopey sister, Caroline, stroked a white rat and pretended she thought the film was silly. His little cousin Tom was pigging out on chocolates and trying to stay awake. Sexy Sophie smoked cigarettes and said nothing. Craig was alternately worrying about the dented Ferrari and watching for a chance to kiss Sophie. Somehow the setting was not romantic enough. But would it get any better?

The vodka surprised him. He had thought her talk of cocktails was just showing off. But she went up the ladder to the hayloft bedroom, where her bag was, and came back down with a half bottle of Smirnoff in her hand. "Who wants some?" she said.

They all did.

The only glasses they had were plastic tumblers decorated with pictures of Pooh and Tigger and Eeyore. There was a fridge with soft drinks and ice. Tom and Caroline mixed their vodka with Coca-Cola. Craig, not sure what to do, copied Sophie and drank it straight with ice. The taste was bitter, but he liked the warm glow as it went down his throat.

The movie was going through a dull patch. Craig said to Sophie, "Do you know what you're getting for Christmas?"

"Two decks and a mixer, so I can deejay. You?"

"Snowboarding holiday. Some guys I know are going to Val d'Isére at Easter, but it's expensive. I've asked for the money. So you want to be a deejay?"

"I think I'd be good at it."

"Is that, like, your career plan?"

"Dunno." Sophie looked scornful. "What's your 'career plan'?"

"Can't make up my mind. I'd love to play football professionally. But then you're finished before you're forty. And anyway, I might not be good enough. I'd really like to be a scientist like Grandpa."

"A bit boring."

"No! He discovers fantastic new drugs, he's his own boss, he makes piles of money, and he drives a Ferrari F50-what's boring?"

She shrugged. "I wouldn't mind the car." She giggled. "Except for the dent."

The thought of the damage he had done to his grandfather's car no longer depressed Craig. He was feeling pleasantly relaxed and carefree. He toyed with the idea of kissing Sophie right now, ignoring the others. What held him back was the thought that she might reject him in front of his sister, which would be humiliating.

He wished he understood girls. No one ever told you anything. His father probably knew all there was to know. Women seemed to take to Hugo instantly, but Craig could not figure out why, and when he asked, his father just laughed. In a rare moment of intimacy with his mother, he had asked her what attracted girls to a man. "Kindness," she had said. That was obviously rubbish. When waitresses and shop assistants responded to his father, grinning at him, blushing, walking away with a distinct wiggle, it was not because they thought he would be kind to them, for God's sake. But what was it? All Craig's friends had surefire theories about sex appeal, and they were all different. One believed that girls liked a guy to be masterful and tell them what to do; another said that if you ignored them they would flock around you; others claimed girls were interested only in an athletic physique, or good looks, or money. Craig was sure they were all wrong, but he had no hypothesis of his own.

Sophie drained her glass. "Another?"

They all had another.

Craig began to realize that the movie was, in fact, hilarious. "That castle is so obviously made of plywood," he said with a chuckle.

Sophie said, "And they all have sixties eye makeup and hairstyles, even though it's set in the Middle Ages."

Caroline suddenly said, "Oh, God, I'm so sleepy." She got to her feet, climbed the ladder with some difficulty, and disappeared.

Craig thought, One down, one to go. Maybe the scene could turn romantic after all.