Satiric adult SF superstar Pratchett (The Last Hero, p. 1254, etc.) resets the Pied Piper tale on Discworld, with predictably unpredictable results. Here the rats themselves are pulling off a profitable scam, masterminded by Maurice the cat. The animals, their intelligence accidentally magically enhanced, infest town after town, until the desperate inhabitants pay their human accomplice to pipe them out. But the rats have developed consciences; and when they agree grudgingly to just one more “plague,” they run up against an evil combining the worst of human and rat natures—and that only human, rat, and cat together can defeat. Much of the charm here resides in the way the animals remain true to their natures—the rats, each with a distinct personality, still fight, steal, and stink, while Maurice is as self-centered as only a cat can be—yet still remain far more appealing than the foolish humans around them. Pratchett hasn’t blunted his wickedly funny pen for younger readers; the only apparent concessions to a teen audience are the adolescent humans abetting the rats, and the story’s relative brevity. He retains the lethal combination of laugh-out-loud farce, razor-sharp satire, and the underlying passionate idealism unique to the confirmed cynic that makes his adult Discworld series so popular. A lot is packed in amidst the humor: ruminations on good and evil, dreaming and doing, leadership and compromise. But this is at heart a story about stories, so necessary as consolations, inspirations, and guides, but also so dangerous when allowed to replace independent thought. Excruciatingly funny, ferociously intelligent. (Fiction. YA)