‘Not all of them. Just one. I narrowed it right down. The net – the net you gave me – was much too wide. It turned up too many names. Too many missing girls. So I looked in the immediate vicinity of Potter’s Field. During school time. In the spring and summer of 1988.’

‘But not all mispers are murder victims, Edie. Some of them – most of them – are just lost contacts. You heard of lost contacts? Did you do lost contacts yet in detective school?’

‘Fine.’ She began to gather up the contents of her thin little file. ‘I’ll do it by myself.’

‘Mispers are sometimes just lost contacts who got out and moved on and changed their name and were bloody happy to get away from whatever nightmare they were stuck in,’ I said.

‘That’s true,’ she conceded. ‘But some mispers end up dead in a basement. Or alive – and that’s even worse. Alive in some bastard’s basement for ten years or more. Chained naked to some fucking wall. And you know that’s true too, don’t you, Max?’

I was silent for a moment.

‘Yes,’ I said.

‘And you were there. You heard what James Sutcliffe told us. There was a girl, Max. It all starts with a girl! Find the girl and you find the killer and you find the motive for it all. But first you have to find the girl. And we have to find the girl, don’t we? We can’t just . . . leave her.’ She stared at me. ‘You really want me to do this thing alone, Max? I can’t believe it. I don’t think that’s who you are.’

‘You don’t know me.’

‘Probably not.’

I walked her to the door.

‘You know the worst thing about being on your own with a kid?’ I said. ‘You care a lot less about the rest of the world. You really wouldn’t believe how much less you care. You just do. Your heart gets hardened. Your world narrows down to you and your child. You want to do this thing off the book?’

She nodded.

‘But why?’ I said. ‘The missing will still be missing. Mallory will still be dead. Bob the Butcher will still be getting marriage proposals sent to his cell.’

‘We do it because if we don’t, they get away with it,’ Wren said. ‘We do it because if we don’t, we’re just like the worst of our kind – too scared to do our job. And we do it because it matters. We do it because it’s right.’

The file slapped hard against my chest.

This time I took it.

‘You have a daughter, Max,’ Wren said. ‘Do it for her.’

When Mrs Murphy arrived I went down to Smiths of Smithfield to look at the file.

There wasn’t much in it. Three sheets of paper.