‘This gun is a big one! A military grade semi-automatic, with a huge magazine. It’s hidden in the trunk of her car. I think I wasn’t supposed to see it. The weird thing about this is that Dearth is supposed to be a place where there’s no crime. That’s what the conference was about. So what does she need a gun like that for? And she calls me a 6/17.’

‘A what?’

‘A 6/17. I think it’s police radio code for a lowly serf. Or a hitch-hiker. Or someone they’re suspicious of.’

‘She’s dropping you off tomorrow at the airport?’ Jo said.

‘Yes.’

‘Well, you won’t see her again after that.’

‘Jo, there’s something you could do for me before I get home. She told me a story this afternoon about a crime she covered up. She seemed proud of it and insisted I had to hear it. She said she thought it would make a good plot for a novel. You know how badly that idea goes down with me.’

‘But you listened anyway,’ Jo said. ‘Of course you did – you always do.’

‘It was difficult. I didn’t have much choice.’

‘Would it work as a novel?’

‘Probably not even as a short story. But I found it interesting. She made me take a recording of it, which I’m glad now I did. It was a murder that happened on Salay Hames, the fifth. About fifteen years ago. Someone had his brains bashed out. I had never heard about it before. I can’t find anything on the internet about it. I looked just now. I’ll get Spoder to look into it for me, of course, but before he does I’d like to know if this murder has made it into the literature. Is there any chance you could have a quick look through the indexes of my reference books and see if there’s anything about the case? Only if you have the time, of course.’

Jo would know the books I meant. I had a small shelf next to my desk: encyclopaedias of crime, transcripts of trials, notable police failures and successes, miscarriages of justice, and so on. All with accessible and useful indexes. They were published for a general audience, but for me they were a first reference source.

‘I don’t mind looking,’ Jo said. ‘But wouldn’t Spoder have access to the police files?’

‘I don’t want to activate the Spoder machine until I’m ready! You know how he rushes around, piles stuff on me, always more than I can manage. Then he comes through with even more. Before Spoder gets interested, I’d like to know what is already known, at least to criminologists. There’s probably nothing about it I can use, but you never know.’