‘Yeah, because we make assumptions only when the specialized nature of our work forces us to. And then we take care to note them.’

Sefton looked between the two of them. Costain had always been the sort of officer who’d insisted on the importance of first-hand street experience, and Ross’ intelligence-based approach always felt that that procedure was missing the wood for the trees, but now … He knew that Costain, when Ross had been unconscious in hospital after the Losley case, had stayed by her bed, had slept in a chair. Sefton had wondered, during those few weeks when Ross had been full of the joys of spring, if they were going to get together. That looked impossible now, which was tough on these two, because he and Quill had someone to talk to about the impossible stresses this team were under, and they didn’t.

Costain picked up a card of his own and drew a squiggly mass of people on it, then he attached it to Spatley with a dotted thread too. ‘Maybe it’s the “spirit” of the riots? Losley said there were two ways to power in London: to “make sacrifice” or “be remembered”, and it’s not like it’s only the old or famous stuff that gets remembered. We hadn’t heard of that green monster thing Kev met. Maybe this is the sort of collective will of those protestors made solid, or something.’

Quill nodded. ‘Good. But I hope that doesn’t bloody turn out to be the case, ’cos it’s going to be hard to nick a manifestation of the collective unconscious.’

Sefton had something to add. ‘All the “ghosts”’ – he made the speech marks gesture – ‘we’ve seen have been really passive. Everything “remembered” as part of what seems to be a sort of collective memory on the part of London just kind of hangs around, in classic haunting fashion. They didn’t hurt anyone. Not even the remembered versions of Losley.’

‘So maybe one of the protestors has made a sacrifice and is deliberately making this happen,’ said Costain.