“So you were just going through the motions?”

“Oh, don’t get me wrong. That might have been why the high-ups wanted the arrest, but my team did a proper job when we interviewed him. There was no evidence whatsoever to suggest Simon Wakefield had anything to do with Emma’s death. His only mistake was getting involved with her in the first place. And I can hardly blame him for that. Like I said, older and wiser men than him had fallen for her charms.” He frowns. “I’ll tell you something that was unusual, though. When most people are caught lying to the police, they cave in pretty quickly. Emma’s response was to tell another lie. It might have been planted in her head by her brief, but even so that’s not a common reaction.”

“How do you think she died?”

“Two possibilities. One, she killed herself. Out of depression?” He shakes his head. “I don’t think so. More likely her lies had caught up with her somehow.”

“And the second?”

“The most obvious one.”

I frown. “What’s that?”

“You don’t seem to have considered the possibility that it was Deon Nelson who killed her.”

It’s true—I’ve been so focused on Edward and Simon, the possibility of it being someone else altogether has hardly crossed my mind.

“Nelson was—probably still is, for all I know—a vicious piece of work,” he continues. “He’s got convictions for violence dating back to when he was twelve. When Emma nearly got him convicted with a made-up story, he’d have wanted revenge.” He’s silent for a moment. “Emma said as much, actually. She told us Nelson was making threats against her.”

“Did you investigate them?”

“We logged them.”

“Is that the same thing?”

“She’d been arrested for wasting police time. You think checking out every allegation she made after that was a top priority? It already looked as if we’d been far too quick to charge Nelson with rape in the first place. What with his lawyer alleging racial harassment, there was no way we were going after him again without firm evidence.”

I think. “Tell me about this video, the one on Emma’s phone. How come you mistook it for rape when it was nothing of the sort?”

“Because it was brutal,” he says flatly. “Maybe I’m old-fashioned. I just can’t see how people can enjoy that kind of thing. But if there’s one thing I’ve learned in twenty-five years’ policing, it’s that you can never understand other people’s sex lives. Young people now, they see this nasty, aggressive porn on the Internet, they think it might be fun to make a video like that on their own phone. Men treating women as objects, women going along with it. Why? It baffles me, it really does. But in Emma’s case, that’s what happened. And with her boyfriend’s best friend, too.”

“Who was that?”

“A man called Saul Aksoy, who worked for the same company Emma did. Nelson’s lawyer got a private investigator to track him down and persuaded him to make a statement. Of course, Aksoy hadn’t broken any laws, but still. What a mess.”

“But if it was Deon Nelson who killed her,” I say, my mind still running on Clarke’s theory, “how did he get into the house?”

“That I don’t know.” Clarke puts down his empty glass. “My bus is in ten minutes. I should go.”

“One Folgate Street has a state-of-the-art security system. That was one of the things Emma liked about it.”

“State-of-the-art?” Clarke snorts. “Maybe ten years ago. These days, we don’t consider anything connected to the Internet high-security. They’re way too easy to hack.”

I suddenly hear Edward’s voice in my head. The shower was on when they found her. She must have been running downstairs with wet feet…

“And why was the shower on?” I say.

Clarke looks confused. “Sorry?”

“The shower—it’s operated by a bangle.” I show him the one on my own wrist. “It recognizes you when you get in and adjusts the water to your personal settings. Then when you get out, it switches itself off again.”

He shrugs. “If you say so.”

“What about the other data from One Folgate Street? The entryphone video and so on? Did you examine that?”

He shakes his head. “By the time she was found, forty-eight hours had passed. The hard drive had wiped itself clean. A lot of security systems do that, to save on disk space. It’s a shame, but there you are.”

“Something happened with the house. That’s got to be part of it.”

“Perhaps. It’s a mystery we’ll never solve now, I suppose.” He stands up and reaches for his grocery bag. I stand too. I’m about to offer him my hand when he surprises me by leaning forward to kiss my cheek. His clothes smell slightly of beer. “Nice to meet you, Jane. And good luck. Frankly I doubt you’ll come across anything we didn’t, but if you do, will you let me know? It still bugs me, what happened to Emma. And not many cases do that.”

THEN: EMMA