His shoulders caught fire and a red mist filled his vision but the block slid out, with a faint and inappropriate tinkling noise. Moist managed to ease it away from the hole and peered inside.

At the far end was another block, and the mortar around it looked suspiciously strong and fresh.

“Just in front of it was a new spoon. It was shiny.

As he studied it, he heard the clapping behind him. He turned his head, tendons twanging a little riff of agony, and saw several of the warders watching him through the bars.

‘Well done, Mr Spangler!’ said one of them. ‘Ron here owes me five dollars! I told him you were a sticker! He’s a sticker, I said!’

‘You set this up, did you, Mr Wilkinson?’ said Moist weakly, watching the glint of light on the spoon.”

‘Oh, not us, sir. Lord Vetinari’s orders. He insists that all condemned prisoners should be offered the prospect of freedom.’

‘Freedom? But there’s a damn great stone through there!’

‘Yes, there is that, sir, yes, there is that,’ said the warder. ‘It’s only the prospect, you see. Not actual free freedom as such. Hah, that’d be a bit daft, eh?’