‘Anyway, I’ve got a bit of a bone to throw you. It’s hardly Interpol but I do some work for women in tight spots,’ she said. ‘Sometimes just helping them sort a problem, sometimes it’s more serious. You can start off expecting one thing and it’s actually something totally different.’ She took another bite. ‘Like, last year, I had a bigamist. His second wife came to me, she had no idea, just knew something wasn’t right. I poked around a bit and that was it. I found him in the Peak District eventually with a whole other family: three kids, cocker spaniel, the lot.’

‘So it’s personal fraud work?’

Maggie shook her head. ‘Not really. Sometimes. It’s all sorts. I’ve had girls about to be sent overseas for marriages arranged by “uncles” who’d basically sold them as British passports – those both came word-of-mouth. One of them lived just round the corner from here, other side of Stratford Road. Her mother was the client – wanted more for her. I got her away, helped set her up elsewhere. Nice girl. She’s in Leeds now, doing a degree – we’re still in touch. I had a girl who was trying to get out of a cult. I’ve also had parents who just wanted to know about their daughter’s dodgy boyfriend. Research.’

‘How long have you been doing it?’

‘As long as I’ve had the business. Since I left the job.’

‘They know?’

‘Of course. And that’s how I get most of the cases. I’ve got a contact – Alan Nuttall, my old DS, DI now – and he rings me if something comes up, a situation where there’s no actual crime, nothing the police can do, or it’s like the bigamist: something’s off and I help find out what. He was prosecuted afterwards, obviously, once it was clear there was a charge to be brought.’

‘You’re a dark horse, Maggie Hammond. I had no idea.’

‘Need-to-know, like I said. And now you do.’

A lot of the Victorian houses Robin knew were Tardis-like, with inner proportions that seemed impossible from the outside, but this one was every bit as small as it had looked from the pavement. Dark, too; there was no fanlight above the front door, and the internal door to the front room was shut, blocking any light that way. As they followed the woman to the kitchen at the back, the phrase ‘down the rabbit hole’ came into her head.