‘Is there a reason that you didn’t remember? I mean, after all, it only happened today,’ says Conway.

‘Concussion?’ I venture.

‘Concussion?’ says Blake. ‘Not amnesia?’

‘I forgot. What can I tell you? I hurt my head. I was taken to hospital. How am I supposed to remember all these details you’re throwing at me?’ I say.

Conway shifts in his seat. ‘If we were to examine your clothes, would we find any blood belonging to the victim?’

‘No,’ I say and then repeat the answer with more confidence. There can’t be any of his blood on me. ‘No. You won’t. So, do your tests and let me go now please.’

Blake seems relieved by my answer and nods meaningfully at Conway.

‘Okay, so before we terminate the interview, you were saying something about witnessing a murder,’ he says. Whatever fight he had seems to have burned away like morning mist.

My brain is telling me to say nothing because I will end up incriminating myself. All I would do is build their case from nothing. They’ve got nothing. They don’t even know about this woman. They can’t put me at the scene. And then it occurs to me: I assumed they were arresting me for what happened to her. That simple, stupid fact has led me wildly into error. I’ve assumed that she was still alive because they didn’t arrest me for murder. But she could be dead.

If her body is found, then what? What if someone saw me? What if I left a print somewhere? They’ve now got my prints from the arrest and my blood will be everywhere at the scene from this wound – the bleeder – the cut above my eye. They are going to nail me to the wall. I know how this works. I have to say something. Besides, I am committed now. I started my interview telling them about seeing a woman being attacked and I can’t now undo that.

‘Yes,’ I say. And then before I know it, I’m telling them about the murder. I tell them about the Victorian-tiled hall and the Tiffany shades. The silk rug that I lay on. How the couple came in, she with her voice tinkling like glass. How I hid while they drank and then argued. How she looked, afterwards, broken on the carpet. How he ran. How I ran.

‘Murder?’ says Conway at one point. ‘You didn’t say it was murder at the start of the interview.’

‘No. I. I thought this was why I was here. For her. And you said grievous bodily harm and I assumed she was alive still,’ I say, stumbling over every word. ‘I’m still not certain. She could be alive, you have to check.’

‘So, she was dead? Then alive and then dead and now alive again?’ Conway says, looking sceptically at Blake.