I wondered if I hadn’t been a bit hasty. Was it better to die in the illusion of sunshine and warmth or face death in a cold darkness of reality? Was it better to die in happy ignorance or terrified knowledge. The answer, if you’re a Londoner, is that it’s better not to die at all.

So that is when I came up with the most ridiculous plan since I’d decided to take a witness statement from a ghost. It was a plan so stupid that even Baldrick would have rejected it out of hand.

I was going to reach out and contact Toby the Dog with my mind. Well not exactly with my mind – that would have been unlikely. Ever since Molly sent me on my little trip down London’s memory lane it had seemed obvious to me that all the accumulated vestigia that seemed to power the ghosts of the city were somehow connected. Information was definitely being passed from location to location. Like a magical internet. How else had I seen so much of the city while my physical body had remained in the Folly? I figured that if I could generate a sort of formless forma, enough to put magic into the stone, it might be possible to create a signal – a beacon that would propagate through the stone memory that might be detected by a particularly sensitive dog of my acquaintance. Who would then bark in an expressive fashion and rush over to Oxford Circus as fast as his little legs would carry him. There he would scamper about snuffling amongst the debris and a particularly intuitive rescue worker would say, ‘Hold up, I think the mutt may be on to something.’

Did I not say it was the most ridiculous plan I’d ever thought of? It had to be Toby because one of the first things I’d done, once Lesley had become an apprentice, was to buy a pack of ESP cards and see if I could use magic to talk mind to mind. So me, Lesley and Dr Walid spent a fun afternoon recreating various bonkers telepathy experiments from the 1960s and ’70s with disappointing results. Even the one experiment where I tried to identify the forma that Lesley was creating didn’t work properly because while I could sense the ‘shape’ in the magic I couldn’t have told you what it was. And besides, even that much only worked when we were less than a metre apart.

That’s what I hate about science – negative results.

But Toby had been proven to be sensitive to magic. And I’d always thought we’d shared a special affinity. And the water was pooling around my ribs and I was getting desperate.