Sergeant Zailer turns her attention to me. ‘Did he tell you he strangled Mary when she was naked? That he left her body in the middle of the bed, in the—’

‘Shut up,’ Aidan snaps.

A violent, sick feeling tears through me, making me gasp. Strangled. Naked.

‘I don’t think he told her,’ says Waterhouse. ‘Something I don’t understand: you did tell Ruth that you killed Mary Trelease years ago. And you told me I’d find the body in the bed if I went to 15 Megson Crescent. Did you really think a dead body might lie undiscovered in a house for years?’

Aidan measures a length of nylon hanging cord and cuts it, as if no one has spoken. He isn’t ignoring Waterhouse—it’s more than that. He’s pretending to be alone in the workshop, wishing us all away. ‘Say something, Aidan!’

‘Why don’t you, if he won’t?’ Charlie Zailer asks me. ‘You lied to me. You said you didn’t know Mary Trelease, but she knows you. She told me she lost you your job, then felt guilty about it and gave you a painting. That true?’

I nod, forcing myself not to look at Aidan. I have no way of knowing how much of the story Mary told her.

‘So you first met Mary when?’

‘Last June.’

‘June. So when Aidan told you in December that he’d killed her years ago, you’d in fact met her six months previously. Presumably you told him he was mistaken. Ruth? Did you tell him that?’

‘I . . .’

‘She told me,’ says Aidan. ‘I told her she was wrong, same as I told DC Gibbs and DC Waterhouse.’

‘Mary Trelease is an artist,’ Waterhouse takes over, and I release the breath I’ve been holding. He isn’t interested in the Spilling Gallery, my run-in with Mary. No one can force me to talk about it if I don’t want to. ‘Your work must bring you into contact with lots of artists. What do you think of them?’

‘Some are all right.’

‘The ones who aren’t—what’s wrong with them?’

Aidan sighs. ‘They treat me like a skivvy.’ He raises his hands. ‘Manual work. It can’t be a skilled profession if you get your hands dirty, that’s what some of them think. You meet them in a restaurant in town and they stare at you blankly—they don’t recognise you clean. When you say hello to them and they make the connection, you can see the shock on their faces: a common labourer in a posh restaurant—who’d have believed it? Then you get the ones who paint the same picture over and over again and think they’ve got a unique style, rather than only one idea, and the ones who only paint in their favourite colours, the same ones they buy all their clothes and carpet their living rooms in.’