The irresistible notion of ''Mystery Men'' is that while Captain Amazing is held captive by his evil, hearty-partying nemesis, Casanova Frankenstein (Geoffrey Rush), a band of nudnick superhero wannabes seize the moment to show their stuff and improve their media profiles. Their stuff, though, is ludicrously dubious: The Blue Raja (Hank Azaria, divinely faux-British) throws cutlery -- but never knives; Mr. Furious (apoplectic Ben Stiller) lives up to his name as a ''ticking time bomb of fury''; The Shoveler (William H. Macy), an earnest Everyman wacky only in his obsession (a great Macy specialty), wields digging implements; The Spleen (Paul Reubens, recycling Pee-wee Herman faces) produces near-lethal flatulence; Invisible Boy (Kel Mitchell) becomes transparent only if no one looks at him; The Bowler (Janeane Garofalo) strikes down adversaries with a ball containing the skull of her dead-but-still-nagging father.
It's a mystery that ''Mystery Men'' ever wrapped at all, given the performers involved, each probably loath to stifle ad-libbed zingers even after Usher yelled ''Cut!'' Of course, Usher could have ditched shtick in the editing, too. But what to lose? The nutty, too-long bit in which Wes Studi, as a bargain-basement Yoda, teaches cooperation by reciting inane aphorisms? The goofy, too-long superhero audition sequence? The clunky, plot-propelling transitions staged on obsessively ornate sets? ''We fight crime. Call it what you will,'' The Shoveler says of his team's claim to superhero status. Call ''Mystery Men'' a sketchbook in search of a movie; it's still a super idea in a summer of flackery.