‘Let’s do that together,’ I said. Alizebeth followed us as we went through the back of the tent into the trailer. It was a dark, confined space, and Bakunin kept apologising. Every scrap of surface, even the untidy flat of his little cot bed, was piled with spares and partly disassembled cameras. There was a musty, chemical stink, mixed with the scent of Penshel seeds. Bakunin’s pipe lay in a small bowl. He reached into a crate under the cot and pulled out several dog-eared record books.

‘Let me see now,’ he began.

There was a door at the end of the little room.

‘What’s through there?’

‘My dark room, along with the file racks for the exposed plates.’

‘It has a door to the outside?’

‘Yes,’ he said.

‘Locked?’

‘No...’

‘You have an assistant then, someone you ordered to hold the door shut?’

‘I have no assistant...’ he said, puzzled.

‘Open this door,’ I told him. He put down the books and went to the communicating door. Just from his body language, I could tell he had been expecting it to open easily.

‘I don’t understand,’ he said. ‘It’s never jammed before.’

‘Stand back,’ I said, and drew Barbarisater. The exposed blade filled the little trailer with ozone, and Bakunin yelped.

I put the blade through the door with one good swing, and ripped it open. There was a loud bang of atmospheric decompression, and foetid air swept over us. A dark, smoky haze drifted out.

‘Emperor of Mankind, what is that?’

‘Warpcraft,’ I said. ‘You say you mix your own oxides and solutions?’

‘Yes.’

‘Where do you get your supplies from?’

‘Everywhere, here and there, sometimes from apothecaries, or market traders or...’

Anywhere. Bakunin had experimented with all manner of compounds over the years to create the best, most effective plates for his camera. He’d never been fussy about where the active ingredients came from. Something in his workshop, something in his rack of flasks and bottles, was tainted.

I took a step towards the darkroom. In the half-light, things were flickering, half-formed and pale. The baleful energies lurking in Bakunin’s workshop could sense I was a threat, and were trying to protect themselves by sealing the doors tight to keep me out.