With the hilarious "Happy Valley," a story originally written by John Cleese and Connie Booth for Monty Python's Flying Circus, this third volume in an extraordinarily popular Mammoth Book series gets off to a suitably silly start. It continues merrily apace with "Attack of the Charlie Chaplins" by Garry Kilworth, visits "The Strawhouse Pavilion" by Ron Goulart, and takes in "A Bad Day on Mount Olympus" with Marilyn Todd. Along the way it introduces Esther Eisner's "Gunsel and Gretel" and Cherith Baldry's "Broadway Barbarian" and renews acquaintance with F. Anstey's "Ferdie." It bemuses as well as amuses with "A Case of Four Fingers" concocted by John Grant, not to mention "The Absolute and Utter Impossibility of the Facts in the Case of the Vanishing of Henning Vok" from Jack Adrian. And before this wildly comic romp ends, it discovers "Math Takes a Holiday" (Paul Di Filippo) and "Mother Duck Strikes Again" (Craig Shaw Gardner). Fantasy finds broad definition in this wackily comic tour. While some of the stories approach the domain of science fiction, others are lodged in an everyday reality. None of them, though, fails to entertain. Together, the more than thirty selections -- thirteen of them brand-new and the balance of them often rare finds or forgotten gems -- provide a fresh sampling of comic genius in the sphere of fantasy fiction and a wide range of tales to suit every taste in humor