All is not right in Toy City: Old nursery rhyme characters -- er, ''Preadolescent Poetic Personalities'' -- are being brutally, and hysterically, murdered. But an oft-soused teddy-bear detective and his new partner, a 13-year-old country boy, are on the case. Rankin's whimsically dense sing-song patter reads like Douglas Adams crossed with Aaron Sorkin by way of Mother Goose -- er, sorry, Madame Goose, as the head of Toy City's classiest brothel prefers to be called. As we (happily) learn of toy theology and (not so happily) of teddy-bear anatomy, Rankin more than lives up to his deliriously inventive title (a reference to the killer's calling card). If he spoils his chance at a timeless classic with a too-topical ending, well, by then we've had much too much fun to really mind.