Cruces was lying a few feet away, fighting for breath and hammering another rack of pipes into the gonne. Vimes managed to pull himself up on to his hands and knees, and gulped air. There was a candle wedged into the wall nearby.

'Got. . . you,' he panted.

Cruces tried to get to his feet, still clutching the gonne.

'You're . . . too old . . . to run . . .' Vimes managed.

Cruces made it up upright, and lurched away. Vimes thought about it. 'I'm too old to run,' he added, and leapt.

The two men rolled in the dust, the gonne between them. It struck Vimes much later that the last thing any man of sense would do was fight an Assassin. They had concealed weapons everywhere. But Cruces wasn't going to let go of the gonne. He held it grimly in both hands, trying to hit Vimes with the barrel or the butt.

Curiously enough, Assassins learned hardly any unarmed combat. They were generally good enough at armed combat not to need it. Gentlemen bore arms; only the lower classes used their hands.

'I've got you,' Vimes panted. 'You're under arrest. Be under arrest, will you?'

But Cruces wouldn't let go. Vimes didn't dare let go; the gonne would be twisted out of his grip. It was pulled backwards and forwards between them in desperate, grunting concentration.

The gonne exploded.

There was a tongue of red fire, a firework stink and a zing-zing noise from three walls. Something struck Vimes' helmet and zinged away towards the ceiling.

Vimes stared at Cruces'contorted features. Then he lowered his head and yanked the gonne hard.

The Assassin screamed and let go, clutching at his nose. Vimes rolled back, gonne in both hands.

It moved. Suddenly the stock was against his shoulder and his finger was on the trigger.

You're mine.

We don't need him any more.

The shock of the voice was so great that he cried out.

He swore afterwards that he didn't pull the trigger. It moved of its own accord, pulling his finger with it. The gonne slammed into his shoulder and a six-inch hole appeared in the wall by the Assassin's head, spraying him with plaster.

Vimes was vaguely aware, through the red mist rising around his vision, of Cruces staggering to a door and lurching through it, slamming it behind him.

All that you hate, all that is wrong – I can put it right.

Vimes reached the door, and tried the handle. It was locked.

He brought the gonne around, not aware of thinking, and let the trigger pull his finger again. A large area of the door and frame became a splinter-bordered hole.

Vimes kicked the rest of it away and followed the gonne.

He was in a passageway. A dozen young men were looking at him in astonishment from half-open doors. They were all wearing black.

He was inside the Assassins' Guild.

A trainee Assassin looked at Vimes with his nostrils.

'Who are you, pray?'

The gonne swung towards him. Vimes managed to haul the barrel upwards just as it fired, and the shot took away a lot Of ceiling.

'The law, you sons of bitchesl' he shouted.

They stared at him.