“We’re hoping that you can help us disentangle some of the facts from the fiction,” said the Mancunian. “You’ve been a recurring motif in his conversation ever since he was sectioned. He’s been very keen to talk to you, but not so much to any of us. He’s also expressed fear of—of repercussions if he confides in anyone and, again, it’s difficult to know whether that fear is part of his illness or, ah, whether there’s someone who he genuinely has reason to fear. Because, ah—”

He hesitated, as though trying to choose his words carefully. Strike said:

“I’d imagine his brother could be scary if he chose to be,” and the psychiatrist seemed relieved to have been understood without breaking confidentiality.

“You know his brother, do you?”

“I’ve met him. Does he visit often?”

“He’s been in a couple of times, but Billy’s often been more distressed and agitated after seeing him. If he seems to be similarly affected during your interview—” said the Mancunian.

“Understood,” said Strike.

“Funny, really, seeing you here,” said Colin, with a faint grin. “We assumed that his fixation with you was all part of his psychosis. An obsession with a celebrity is quite common with these kinds of disorders… As a matter of fact,” he said candidly, “just a couple of days ago, Kamila and I were agreeing that his fixation with you would preclude an early discharge. Lucky you called, really.”

“Yeah,” said Strike drily, “that is lucky.”

The redheaded male nurse knocked on the door and put his head in.

“That’s Billy ready to talk to Mr. Strike.”

“Great,” said the female psychiatrist. “Eddie, could we get some tea in here? Tea?” she asked Strike over her shoulder. He nodded. She opened the door. “Come in, Billy.”

And there he was: Billy Knight, wearing a gray sweatshirt and jogging pants, his feet in hospital slippers. The sunken eyes were still deeply shadowed, and at some point since he and Strike had last seen each other, he had shaven his head. The finger and thumb of his left hand were bandaged. Even through the tracksuit that somebody, presumably Jimmy, had brought him to wear, Strike could tell that he was underweight, but while his fingernails were bitten to bloody stubs and there was an angry sore at the corner of his mouth, there was no longer an animal stench about him. He shuffled inside the interview room, staring at Strike, then held out a bony hand, which Strike shook. Billy addressed the doctors.

“Are you two going to stay?”

“Yes,” said Colin, “but don’t worry. We’re going to keep quiet. You can say whatever you like to Mr. Strike.”

Kamila positioned two chairs against the wall and Strike and Billy sat down opposite each other, the desk between them. Strike could have wished for a less formal configuration of furniture, but his experience in Special Investigation Branch had taught him that a solid barrier between questioner and interviewee was often useful, and doubtless this was just as true on a locked psychiatric ward.

“I’ve been trying to find you, since you first came to see me,” Strike said. “I’ve been quite worried about you.”

“Yeah,” said Billy. “Sorry.”

“Can you remember what you said to me at the office?”

Absently, it seemed, Billy touched his nose and his sternum, but it was a ghost of the tic he had exhibited in Denmark Street, and almost as though he sought to remind himself how he had felt then.

“Yeah,” he said, with a small, humorless smile. “I told you about the kid, up by the horse. The one I saw strangled.”

“D’you still think you witnessed a child being strangled?” asked Strike.

Billy raised a forefinger to his mouth, gnawed at the nail and nodded.

“Yeah,” he said, removing the finger. “I saw it. Jimmy says I imagined it because I’m—you know. Ill. You know Jimmy, don’t you? Went to the White Horse after him, didn’t you?” Strike nodded. “He was fucking livid. White Horse,” said Billy, with a sudden laugh. “That’s funny. Shit, that’s funny. I never even thought of that before.”

“You told me you saw a child killed ‘up by the horse.’ Which horse did you mean?”

“White Horse of Uffington,” said Billy. “Big chalk figure, up on the hill, near where I grew up. Doesn’t look like a horse. More like a dragon and it’s on Dragon Hill, as well. I’ve never understood why they all say it’s a horse.”

“Can you tell me exactly what you saw up there?”

Like the skeletal girl Strike had just passed, he had the impression that Billy was staring inside himself, and that outer reality had temporarily ceased to exist for him. Finally, he said quietly:

“I was a little kid, proper little. I think they’d given me something. I felt sick and ill, like I was dreaming, slow and groggy, and they kept trying to make me repeat words and stuff and I couldn’t speak properly and they all thought it was funny. I fell over in the grass on the way up. One of them carried me for a bit. I wanted to sleep.”

“You think you’d been given drugs?”

“Yeah,” said Billy dully. “Hash, probably, Jimmy usually had some. I think Jimmy took me up the hill with them to keep my father from knowing what they’d done.”

“Who do you mean by ‘they’?”

“I don’t know,” said Billy simply. “Grown-ups. Jimmy’s ten years older’n me. Dad used to make him look after me all the time, if he was out with his drinking mates. This lot came to the house in the night and I woke up. One of them gave me a yogurt to eat. There was another little kid there. A girl. And then we all went out in a car… I didn’t want to go. I felt sick. I was crying but Jimmy belted me.

“And we went to the horse in the dark. Me and the little girl were the only kids. She was howling,” said Jimmy and the skin of his gaunt face seemed to shrink more tightly to his bones as he said it. “Screaming for her mum and he said, ‘Your mum can’t hear you now, she’s gone.’”

“Who said that?” asked Strike.

“Him,” whispered Billy. “The one that strangled her.”

The door opened and a new nurse brought in tea.

“Here we go,” she said brightly, her eager eyes on Strike. The male psychiatrist frowned at her slightly and she withdrew, closing the door again.

“Nobody’s ever believed me,” said Billy, and Strike heard the underlying plea. “I’ve tried to remember more, I wish I could, if I’ve got to think about it all the time I wish I could remember more of it.

“He strangled her to stop her making a noise. I don’t think he meant it to go that far. They all panicked. I can remember someone shouting ‘You’ve killed her!’… or him,” Billy said quietly. “Jimmy said afterwards it was a boy, but he won’t admit that now. Says I’m making it all up. ‘Why would I say it was a boy when none of it ever fucking happened, you’re mental.’ It was a girl,” said Billy stubbornly. “I don’t know why he tried to say it wasn’t. They called her a girl’s name. I can’t remember what it was, but it was a girl.