I won’t lie, I’ve seen him look keener. So I tried to stay calm as I laid it all out and not let on how fired up I was. I told him about the drugs that had been smuggled out of the ward after being given to Kevin by an insider (with a healthy percentage presumably coming back to that same insider once they’d been sold). I told him about the irrelevance of the camera on Kevin’s corridor, the time when it was on and when it wasn’t. Finally, I told him what had happened to Shaun – or, to be accurate, what had been done to him to ensure that he couldn’t tell anyone what he knew.

I asked Banksy for another cigarette when I’d finished.

I lit up and waited.

‘So, why kill Kevin?’ he asked, finally. ‘You know, if there’s this cushy little drug thing going which presumably everyone’s doing very nicely out of. Why scupper it?’

‘I don’t think Kevin wanted to do it any more.’

‘You’re just guessing though, right?’

‘Look, I know him and Shaun had been arguing and I think that’s because Shaun wanted him to stop. In the end Shaun got his way, so Kevin told everyone involved that he wanted out. That’s why all those drugs were found in his room, because he wasn’t passing them on to his connections any more. He’d had enough.’

‘So they decided to kill him, that’s what you’re saying?’

‘Yeah, maybe they did . . . his connections on the outside.’ I held up a finger. ‘Or maybe it was just one person’s decision.’ Banksy nodded. He already knew who I was talking about of course, because I hadn’t wasted any time in telling him who had killed Kevin. ‘What about if Kevin had been stockpiling those drugs? Holding on to them as some kind of insurance policy or something?’ Then another idea struck me which suddenly made perfect sense. ‘Maybe he was using those drugs to blackmail her.’

‘Seriously?’

‘Why not? Or at least planning to down the road.’ I was a bit annoyed with myself for not working this out before, but I wasn’t going to blame myself for not being match-fit after everything that had happened. ‘Sounds like a pretty decent motive to me.’

‘How come she didn’t take the drugs, then? When she killed him?’

I shrugged. ‘Couldn’t find them.’ I still didn’t know exactly where in Kevin’s room the drugs had been hidden. ‘She certainly wouldn’t have had much time to go looking for them, turn his room over, whatever. A couple of minutes, that’s all she would have been in there for. In, pillow over his face, and out again.’

Bitch, I thought. Stone cold bitch.