‘You’re not a shrink,’ I tell her. She hates Aidan. Hates him more than anything. With this insight, the conspiracy I’ve constructed in my mind—Mary and Aidan against me—starts to dissolve. At first I’m relieved—I can forgive him anything but that, anything at all, I know I can—but the respite doesn’t last long. Not good enough, I think to myself. Not the same as being able to forgive him anything, not unconditional.

‘I could be a shrink,’ says Mary. ‘I don’t believe I’d need any training whatsoever. All I’d need is experience, which I’ve got, and a brain, which I’ve got.’

‘We made a deal. I’ve told you everything.’

‘No, you haven’t.’

How does she know? My mind fills with all the things I’ve kept back: the Access 2 Art fair, Aidan’s prediction about the nine paintings, his insistence that I bring Abberton to him as proof. Proof that he didn’t murder Mary. Why would anyone who knew they’d strangled someone demand to see proof that they hadn’t? Sometimes, because my understanding nothing has become normal, I forget how little sense it all makes. Then I remember again and am as shocked as if I were realising it for the first time.

‘We made a deal,’ I say again.

Mary lets air out through clenched teeth, a hiss of disgust. ‘You’re here because you want the truth about Aidan. You think I must be able to explain it to you. You don’t care how bad it is—you want to know.’

‘That’s right.’

‘You’ve still got a choice. You could leave this house, forget him, forget about Martha. Forget me. The safe option.’

‘I don’t want to be safe. I want to know.’

‘I don’t know Aidan Seed,’ says Mary, looking past me into the distance.

No. Not possible.

‘I used to, though. I knew him a long time ago.’

‘I haven’t seen Aidan since the day Martha died. The tenth of April, 2000.’ Mary puts my letter down on the table and bends over it, pushing her bushy hair out of her eyes. ‘When were your seventy-two hours?’

I don’t need to ask what she means. To me, that number will only ever mean one thing. ‘Later.’ I force myself to give her one more piece of information, of my life. ‘It started on April the twenty-second.’

‘Close enough,’ she says. Then her face goes blank. ‘Aidan was there when Martha jumped.’

I hardly dare to breathe.

‘He also didn’t stop her.’

‘You were there too?’