There was a book opened, its middle pages inked with tiny drawings of the human figure, and a sketch that might have been a man, might have been a monkey, or something in between like the Missing Link or so-called Nondescript that had been displayed in London a few years ago. Beyond was a wall lined with shelves and stocked with stoppered bottles and things in jars. Each was labelled – Latin words I knew nothing of, but I took care not to look too closely. There was Crillick’s white coat hanging up, others too, and I remembered a conversation about one of Crillick and Vincent’s friends who was an amateur in something they’d called ethnology. Had he been one of those three men who had debated, calm as you like, the best means of removing the Leopard Lady’s colour?

I looked around, listening intently. I was yet to find a soul, had not heard a sound. A coldness washed over me that Black Bill had been wrong, and that Crillick didn’t keep his prisoners here after all, and then I smelt something rotten beneath the freshness. I followed the smell to the far side of the room where an intricately woven tapestry hung from the wall. I still couldn’t quite put my finger on what it was, but this was definitely where it was coming from. I pulled at the tapestry and it came away in my hand. At last, I had found out where they were keeping her!

The stench as I yanked open the final door was like when I walked into St Giles, but worse for being all the more concentrated. Human beings in cramped conditions, mingled with excrement and layered with fear. And there was a sort of sweetness to it too. The night I had visited the West India Docks, this is what it had been like. The room was small, about twelve feet long and narrow with it. There were bunks on either side. As I walked along, I saw hunched forms in them. It wasn’t late but down here with no windows there was no way to tell day from night. Maybe that’s why they slept. Each bunk had room for two and there was one more cage.