‘You must be Ruth Bussey. DC Simon Waterhouse, Culver Valley CID.’ He opens a small wallet and shows me his police identification. He’s a heavy, rough-faced man with big hands and too-short trousers that don’t quite reach the tops of his shoes.

Sergeant Zailer smiles at me. She says nothing about my coat and I don’t ask. She hasn’t brought it with her. When she tells Aidan her name, I will him not to look at me, not to let his surprise show. ‘Okay if we have a chat?’ she says.

‘I’ve got work to do.’ Aidan doesn’t sound surprised, only sullen.

‘It won’t take long.’

‘I talked to him on Saturday.’ Aidan jerks his head in Waterhouse’s direction. ‘I’ve got nothing to add to what I said then.’

‘Have a guess where I spent most of this morning?’ Charlie Zailer’s tone is soothing and teasing at the same time.

‘No, thanks.’

‘Fifteen Megson Crescent.’

This is followed by a long silence. DC Waterhouse and I look at one another, wondering if one of us will have to break it; at least, that’s what I’m wondering.

‘Fifteen Megson Crescent is where Mary Trelease lives. That’s who I spent the morning with: Mary Trelease.’

Aidan gives her a cold look. ‘How can a dead woman live anywhere?’ he says. ‘I killed her.’

Sergeant Zailer nods. ‘Simon—that’s DC Waterhouse—he told me you’ve convinced yourself of that. I can assure you, you’re wrong. I met Mary Trelease, spoke to her, saw her breathing and moving around.’

Aidan pulls the underpinner towards him, takes two mitred frame edges and puts them in the machine. Back to work.

‘Do you think I’m lying?’

I can’t stand the stifling tension in the air. ‘Aidan, answer her!’

‘If you hop in the back of my car, I’ll take you to her house so that you can see for yourself that she’s fine.’

‘No.’

‘How did you meet Mary?’ Sergeant Zailer’s voice is gently insistent. ‘You didn’t tell Simon the full story, did you? Will you tell it to me?’

‘No.’

‘Mary says she’s never met you. Which, if she’s telling the truth, means you’ve never met her.’

He looks up, angry to have his attention taken away from his underpinning. ‘If I killed her, I must have met her. It’s simple logic.’ How can he be angry? How does he expect the police to react?

‘Okay,’ says Sergeant Zailer. ‘So tell me about meeting Mary.’

Silence. I stare at him, silently urging him to answer, knowing he won’t. My last hope is disintegrating and there’s nothing I can do. Nobody can help if Aidan won’t talk, not even the police.

‘Aidan? How many times did you and Mary meet before you killed her?’

‘He hasn’t killed anybody,’ I say, starting to cry.