On a crooked world with crooked buildings, a farmer hunts a big purple bird with a blunderbuss. Just as he seems to have cornered the sneaky pest, a big blue box appears on the cliff top, and a two strange men step out. Confused, the farmer shoots one of them directly in the chest, and is even more confused when he seems genuinely hurt by this, instead of just going black and crispy for a few minutes. The TARDIS has landed on a bizarre world, upon which everything conforms to cartoon logic. Its denizens cannot be hurt of killed, only knocked out of shape; gravity works only by consent; and evil deeds, particularly those involving sticks of dynamite, always rebound on the people who commit them. But the TARDIS�s arrival brings change to the crooked world. New concepts are introduced, and people start to question why they have always acted the way they do. Cats are no longer sure whether they want to chase mice, and a teenage pop band begins to get tired of the way its van always breaks down in spooky woods and foggy areas. And worse, the cartoon logic starts to crumble under scrutiny. People can really be injured and die, and no one knows how to deal with this. As the inhabitants of the crooked world face up to their changed existence, the Doctor has to watch the damage his arrival has caused, hoping only that he can guide these people to use their new freedoms wisely.