'Ow!'

'—mind your head. Sorry.'

Rubbing his head with one hand, Vimes used the other to examine the hole in the plaster.

'There's . . . something in here,' he said. 'Pass me one of those chisels.'

There was silence.

'A chisel, please. If it makes you feel any better, we are trying to find out who killed Mr Hammerhock. All right?'

Carrot picked one up, but with considerable reluctance.

'This is Mr Hammerhock's chisel, this is,' he said reproachfully.

'Corporal Carrot, will you stop being a dwarf for two seconds? You're a guard! And give me the damn chisel! It's been a long day! Thank you!'

Vimes prised at the brickwork, and a rough disc of lead dropped into his hand.

'Slingshot?' said Carrot.

'No room in here,' said Vimes. 'Anyway, how the hell could it get this far into the wall?'

He slipped the disc into his pocket.

'That seems about it, then,' he said, straightening up. 'We'd better – ow! – oh, fish out that clockwork soldier, will you? Better leave the place tidy.'

Carrot scrabbled in the darkness under the bench. There was a rustling noise.

'There's a piece of paper under here, sir.'

Carrot emerged, waving a small yellowing sheet. Vimes squinted at it.

'Looks like nonsense to me,' he said, eventually. 'It's not dwarfish, I know that. But these symbols – these things I've seen before. Or something like them.' He passed the paper back to Carrot. 'What can you make of it?'

Carrot frowned. 'I could make a hat,' he said, 'or a boat. Or a sort of chrysanthemum—'

'I mean the symbols. These symbols, just here.'

'Dunno, captain. They do look familiar, though. Sort of . . . like alchemists' writing?'

'Oh, no!' Vimes put his hands over his eyes. 'Not the bloody alchemists! Oh, no! Not that bloody gang of mad firework merchants! I can take the Assassins, but not those idiots! No! Please! What time is it?'

Carrot glanced at the hourglass on his belt. 'About half past eleven, captain.'

'Then I'm off to bed. Those clowns can wait until tomorrow. You could make me a happy man by telling me that this paper belonged to Hammerhock.'

'Doubt it, sir.'

'Me too. Come on. Let's go out through the back door.'

Carrot squeezed through.

'Mind your head, sir.'

Vimes, almost on his knees, stopped and stared at the doorframe.

'Well, corporal,' he said eventually, 'we know it wasn't a troll that did it, don't we? Two reasons. One, a troll couldn't get through this door, it's dwarf sized.'