I say it as if I think Tom Ellis is crazy, as if the idea is so preposterous I can’t believe it. But actually I can. That is, I know Edward’s capable of anything that he decides to do.

You say just, Ellis says flatly. There is no just with Edward Monkford. Nothing’s more important to him than getting his own way. Oh, I don’t doubt he loved Elizabeth, after his own fashion. But I don’t think he cared for her, if you see what I mean. Did you know there’s a species of shark so vicious, their embryos eat one another in the womb? As soon as they develop their first teeth, they turn on one another until only the biggest one’s left, and that’s the one that gets born. Edward’s like that. He can’t help himself. To challenge him is to be destroyed by him.

Did you tell the police any of this?

Tom Ellis’s eyes look haunted. No, he admits.

Why not?

After the inquest, Edward went away. Later we heard he was living in Japan. He wasn’t even working as an architect, just supporting himself with odd jobs. David and I thought we’d seen the last of him.

But he came back, I say.

Eventually, yes. One day he walked into the office as if nothing had happened and announced that from now on the Partnership would be going in a new direction. He cleverly pitched it to David as a fusion of visual simplicity and new technology, and persuaded him that I was standing in the way. It was his revenge on me for taking Elizabeth’s side against him.

So while he was away, I say, you didn’t want any scandal because you thought the Partnership was all yours. That’s why you kept quiet.

Tom Ellis shrugs. That’s one interpretation.

It sounds to me as if you were trying to piggyback off Edward’s talent.

Think what you like. But I agreed to talk to you because you said you were scared.

I didn’t say I was scared. I’m curious about him, that’s all.

Christ. You’re in love with him too, aren’t you? Tom Ellis says sourly, staring at me. I don’t know how he does it—how he mesmerizes women like you. Even when I tell you he killed his own wife and child, you aren’t disgusted. It’s almost like it excites you—makes you think he really is some kind of genius. When all he really is, is a baby shark in the womb.

NOW: JANE

It takes a bit more detective work to track down Simon Wakefield. I manage to speak to Mark, the agent who dealt with One Folgate Street before Camilla, but he doesn’t know how to contact Emma’s former boyfriend either.

“If you do speak to him, though,” he says, “give him my best, will you? It was tough, what happened to him.”

“Emma’s death, you mean?”

“That too. But even before then, with the break-in at their previous flat and so on.”

“They were burgled? I didn’t know that.”

“That was why they wanted One Folgate Street in the first place, for the security.” He pauses. “Ironic, when you think about it. But Simon would have done anything for Emma. He wasn’t particularly keen on living there himself, but as soon as she said she liked it, that was that. The police asked me if I’d ever seen any evidence he could be violent toward her. I told them no way. He adored her.”

It takes me a moment to understand what he’s saying. “Hang on. The police thought Simon might have killed her?”

“Well, they didn’t say so explicitly. But I had to liaise with them after she died, letting the forensics teams into the house and so on, so I got to know the detective running the investigation quite well. He was the one who asked about Simon. Apparently Emma had claimed he’d physically hurt her.” He lowers his voice. “I was never really sure about Emma, to be honest. Everything was all about her, if you know what I mean. Bit of a drama queen. It seemed like Simon didn’t get much say in things.”

Mark might not have his contact details, but he remembers where Simon worked, and that’s enough information for me to track him down on LinkedIn. The magazine he wrote for has closed now, and like most freelancers he keeps his profile and CV publicly searchable. Even so, I hesitate before contacting him. Yes, he might have left flowers for Emma outside One Folgate Street, but from what Mark just told me, Simon had also been a suspect in her death. How sensible is it, really, to start questioning him about what happened?

I will be careful, I decide, and make sure I don’t press or threaten him in any way. So far as he’s concerned, I’ll simply be trying to make amends for taking his floral tributes.

I send a bland email, asking if we can meet for a chat. A reply comes back within minutes, suggesting Costa Coffee in Hendon.

I’m early, but he is too. He arrives dressed much as he was that time outside One Folgate Street: polo shirt, chinos, trendy shoes; the smart-casual uniform of the London media worker. He has a pleasant, open face, but his eyes are troubled as he takes a seat opposite me, as if he knows this is going to be difficult.