‘That'll happen in just two years?’

‘Oh, no. That'll happen within a few minutes, sir. You see, magic isn't just coloured lights and balls. Magic holds the world together.’

In the sudden silence, Lord Vetinari's voice sounded crisp and clear.

‘Is there anyone who knows anything about Ghengiz Cohen?’ he said. ‘And is there anyone who can tell us why, before leaving the city, he and his men kidnapped a harmless minstrel from our embassy? Explosives, yes, very barbaric… but why a minstrel? Can anyone tell me?’

There was a bitter wind this close to Cori Celesti. From here the world mountain, which looked like a needle from afar, was a raw and ragged cascade of ascending peaks. The central spire was lost in a haze of snow crystals, miles high. The sun sparkled on them. Several elderly men sat huddled around a fire.

‘I hope he's right about the stair of light,’ said Boy Willie. ‘We're going to look real muffins if it isn't there.’

‘He was right about the giant walrus,’ said Truckle the Uncivil.

‘When?’

‘Remember when we were crossing the ice? When he shouted, “Look out! We're going to be attacked by a giant walrus!”’

‘Oh, yeah.’

Willie looked back up at the spire. The air seemed thinner already, the colours deeper, making him feel that he could reach up and touch the sky. ‘Anyone know if there's a lavatory at the top?’ he said.

‘Oh, there's got to be,’ said Caleb the Ripper. ‘Yeah, I'm sure I heard tell about it. The Toilet of the Gods.’

‘Whut?’

They turned to what appeared to be a pile of furs on wheels. When the eye knew what it was looking for this became an ancient wheelchair, mounted on skis and covered with rags of blanket and animal skins. A pair of beady, animal eyes peered out suspiciously from the heap.