When Starbucks tries to open another coffee shop -- its 17th -- within the pages of the Hardy Boys series, Thursday Next cracks down. She's the literary detective keeping the peace in this fourth installment of Jasper Fforde's hyper-imaginative sci-fi comedy series Something Rotten, set in an England where everybody is jumping in and out of books. Facing off against an evil ''escaped fictionaut'' named Yorrick Kaine, Next must find a cloned Shakespeare, pronto (or else ''Hamlet'' is lost forever), and help the good guys win a climactic match of a Quidditch-y game called SuperHoop (or else thermonuclear war ensues). Fforde has churned this quartet of books out at a clip -- the first, ''The Eyre Affair,'' hit in 2002 -- and the essential one-jokeness of the premise is starting to show. But he compensates with enough furious daft invention to sate his cult fan base.