“Uh-oh,” said Jolly. “We’ve done it now.”

As they watched, Miss Muffet started to make her way to the stairs. She had obviously decided that someone had to pay for the destruction of her spider, but they were distracted from her approach by the ringmaster. His wooden face had contorted into a mask of rage. Thin streams of black smoke poured from his nostrils. Beside him, the Ferris wheel rattled on its foundations. Bolts popped, and its supports collapsed. The Ferris wheel dropped to the floor and headed toward them.

“Incoming!” shouted Jolly.

Samuel and the dwarfs dived out of the way of the rolling wheel. Samuel was relieved to see Lucy and the policemen do the same. They reacted fast, certainly faster than Miss Muffet, who reached the top of the stairs just in time to be hit by the wheel. It rolled halfway down the stairs before striking a wall at full speed, tearing through the brickwork and taking Miss Muffet with it. All that was left to show she had ever been there at all was a trail of crushed black spiders.

And that was when the Polite Monster appeared.

To start with, Samuel and the others didn’t know that he was polite. When monsters appear, the general approach is to assume that they don’t mean anyone any good and to set about getting rid of them. If that doesn’t work, it’s a good idea to make your apologies and leave while you still can. The Polite Monster had a lot of horns, and a great many teeth in its jaws, and four eyes, two on each side of its head. It was about twelve feet tall, and almost as wide, and was covered entirely in coarse red fur. It popped into existence in a puff of purple and yellow smoke, accompanied by the most horrendous smell combining the worst aspects of rotting fish, dog poo, and very old eggs that had been scrambled and fed to someone with bad digestion and worse wind.

The Polite Monster sniffed the air, made a face, and said, “That wasn’t me.”

It had a very cultured voice. It sounded like a monster that liked light opera, and perhaps acted in plays for the local dramatic society, the kind in which chaps called Gussy popped up dressed in tennis whites, and people laughed like this: “I say, aha-ha-ha!”

By that point, everyone who wasn’t a monster had found somewhere to hide. This floor of the shop was devoted entirely to books and some more board games, which had been a relief to everyone until the Polite Monster appeared. There was a limit to how much damage a game of Scrabble could inflict: at worst, it could probably arrange some of its tiles into a rude name.

“Hello?” said the Polite Monster. “Anybody home?”

Samuel poked his head up from behind a pile of boxes of Risk. The boxes were rattling alarmingly, suggesting to Samuel that some games might be more dangerous than others. This was confirmed when he heard a muffled shot from the topmost box, and a tiny cannonball pierced the lid and flew past his ear. A very small voice, muffled by cardboard, shouted, “Reload!”