‘Then I started getting messages from her, saying I looked really fit in my pictures.’ He laughed humourlessly. ‘So I made the mistake of responding, didn’t I? Flirting. I mean, I thought it was just a bit of harmless fun. I wasn’t going to do anything.’ He sighed. ‘Then she suggested meeting up and I said yes.’ He pulled a face. ‘That’s the bit my missus is upset about. But I really wasn’t intending to do anything. I was just, I don’t know, curious.’

He fiddled with a cigarette packet as he spoke, turning it over and round in his hands, picking at the edges, the gruesome image of a man with a throat tumour rotating in front of my eyes.

‘Except she didn’t turn up, which to be honest was a massive relief. I went home and the next day the police turn up and show me that website. They’ve got all these screenshots from Facebook—’

‘I’ve seen it,’ I said.

‘I thought you might have. But the screenshots were Photoshopped and Sarah Smith’s profile was changed to that of a twelve-year-old girl. Same profile but new photo, new age, new everything. And there were photos of me at the meeting point, lurking about looking shifty. Someone must have been taking pictures of me with a long-lens camera.’

‘Oh my God.’

‘Yeah. Anyway, the police tracked down the IP address of this Sarah Smith, who was obviously a made-up person, to an internet cafe here in Brixton. No CCTV or anything, though, not that the police are really that interested.’

‘Is that why you’re here?’

He nodded. ‘I wanted to check the place out. See if I saw anyone I recognised. But no joy, just a load of students.’

‘What about the images on your computer?’

He rubbed his face. ‘Christ. The police showed me the pictures. I’m never going to get over it, mate. Little kids . . . Actually, I can’t even talk about it. Heartbreaking stuff. The kind of stuff that makes you want to seriously hurt the people responsible.’

‘I don’t even want to imagine it.’

‘Vile stuff. Anyway, the police accept that they have no evidence that it was me who downloaded the pictures. Loads of people have access to my computer – the cleaners, the IT department. Plus we had a break-in a few days before this all happened. I didn’t report it because nothing got nicked and I didn’t want the hassle. So the police thought I was lying at first.’ He sighed. ‘Anyway, my lawyer was able to persuade them they didn’t have a leg to stand on and they’ve finally dropped the case.’

‘Thank God for that.’

‘Too right. Come on, let’s go outside. I need one of these.’