The Amazing Maurice and His Educated Rodents (Discworld 28)

Maurice and the rats have teamed up with a young lad named Keith to implement a clever moneymaking scheme. Upon entering a town, the rats make a general nuisance of themselves -- stealing food and widdling on things -- until the townsfolk become desperate to get rid of them. Then Maurice and Keith appear on the scene and offer to save the day by ridding the town of its infestation for a small fee. It seems like a surefire plan until the group arrives in the town of Bad Blintz and gets hooked up with Malicia, a young girl with a vivid imagination and a knack for finding trouble. When it's discovered that Bad Blintz already has a rat problem -- one that a couple of shifty-eyed rat catchers claim to have under control -- things turn deadly. For lurking beneath the town's streets is an obstacle course of mangling rattraps and noxious poisons. And beyond that is a monster so powerful and ugly, even Malicia couldn't imagine it.

As Maurice and the rats battle for their very survival, a number of provocative themes surface: life after death, good versus evil, and the sacrifice of the few for the many.