Theatre of Cruelty (Terry Pratchett)

It wasn't easy, being the senior policeman in Ankh-Morpork, greatest of cities of the Discworld.^[1]

There were probably worlds, captain Vimes mused in his gloomier moments, where there weren't wizards (who made locked room mysteries commonplace) or zombies (murder cases were really strange when the victim could be the chief witness) and where dogs could be relied on to do nothing in the night time and not go around chatting to people. Captain Vimes believed in logic, in much the same way as a man in a desert believed in ice -- i.e., it was something he really needed, but this just wasn't the world for it. Just once, he thought, it'd be nice to solve something.

He looked at the blue-faced body on the slab, and felt a tiny flicker of excitement. There were clues. He'd never seen proper clues before.

"Couldn't have been a robber, Captain," said Sergeant Colon. "The reason being, his pockets were full of money. Eleven dollars."

"I wouldn't call that full," said Captain Vimes.

"It was all in pennies and ha'pennies, sir. I'm amazed his trousers stood the strain. And I have cunningly detected the fact that he was a showman, sir. He had some cards in his pocket, sir. 'Chas Slumber, Children's Entertainer'."

"I suppose no one saw anything?" said Vimes.

"Well, sir," said Sergeant Colon helpfully, "I told young Constable Carrot to find some witnesses."

"You asked Corporal Carrot to investigate a murder? All by himself?" said Vimes.

The sergeant scratched his head.

"And he said to me, did I know anyone very old and seriously ill?"