‘Yes.’ I stand up, pace around and sit down again. ‘I chucked my drink all over him and then took his photo because I thought Troy might have recognized him from twenty years ago. It was a long shot, but you never know.’ I’m still trying to calm myself. ‘What were you two doing in here? Are those screwdrivers?’

‘Yeah,’ says Ariel. ‘Joe. We have things to tell you.’

I register the tone of her voice, so I focus on what they’re trying to say.

‘I’ve been in here today with my dad,’ says Troy. ‘He was working so he couldn’t spend much time on it, but he told me which panels were hollow and let me borrow his tools. He thinks I’m mad, but that’s OK. He already did. A son of his changing his surname. There’s no coming back from that with him.’

‘I came over a couple of hours ago,’ says Ariel. ‘Troy and I arranged it all yesterday.’

I tell myself not to be jealous of them doing things without me. They are alive and I’m not. And they’re doing it for me, even though I’m not sure I want them to.

‘Troy and I have been talking a lot about this. Since there was never any sighting of anyone taking anything that could have been a body out of this place, we thought maybe –’ She has to stop, overcome.

‘We thought you might not have gone anywhere,’ Troy says. ‘It was just an idea, but this is a strange building, and maybe you went out through some kind of heating vent thing, or maybe you’re still in it somewhere. Maybe that’s why you always come back here, every day, no matter what. This room was never part of the investigation. We know about it, but hardly anyone else does. All they know is that you were seen on CCTV outside Boots. Then they dredged the river and did what they could with the sea, but we’re not sure anyone ever looked right here.’

I nod. I don’t know what to say.

‘You can’t see it, can you?’ says Ariel. ‘We’ve taken the wood panelling off this wall. Is it there in your world? Is there a panel of wood painted white?’

I look at where she’s pointing, at the panel of wood, shiny white with a smiley face drawn on it.

‘Yes. It looks quite new.’

‘Amazing,’ says Troy. ‘Because now it looks really old. It doesn’t look as if it’s been repainted, or replaced in the past twenty years, and it has graffiti and stuff on it.’

‘We’ve unscrewed it,’ says Ariel. ‘And we’ve just got the front bit right off. I wrote some of that graffiti – that bit about my dad.’ She touches it, and for the first time I see it.