In Number9dream, Eiji Miyake is an archetypal orphan. His mom is in a mental clinic, and he’s come from provincial Japan to Tokyo to hunt down his powerful father. Eiji’s quest leads him through an underworld of skull-bashing gangsters and Popsicle-twiddling nymphets scarcely distinguishable from his own manga-fied, Hollywoodized imagination. (David Mitchell writes, with typical neon voluptuousness, of a nightclub ”so thick with sweat, smoke, and sheer din you could swim up to the mirror-balls on the disco ceiling.”) Mitchell is a hardened intertextual wiseass, alluding to ”Blade Runner” and Haruki Murakami novels, then winking at the allusions. He borrows his title from a John Lennon song, but the effect is all ”Revolution 9.” It is destined to annoy, but delirious — a grand blur of overwhelming sensation.