If you need to look down on others to feel better about yourself, “Napoleon Dynamite” is the movie for you. A success at Sundance, the feature debut of writer-director Jared Hess is a supremely condescending look at dimwits and misfits in a tiny Idaho hamlet, most notably the ultra-geeky title character, a lanky high school student, and his family and friends. It might be fun if there were any sign of affection or respect in the makers’ approach to the doltish figures on display, but there isn’t; an attitude of smug contempt dominates instead. Though there are some easy laughs scattered throughout, as a whole it’s the sort of movie that leaves a bad taste in your mouth.

Napoleon is played by Jon Heder as a gawky, squinting, perpetually dyspeptic kid with a shock of frizzy orange hair, who’s virtually a pariah on campus, relentlessly picked on by the guys and ignored or insulted by the girls. He lives with his grandma, a hard-bitten old broad, and his older brother Kip (Aaron Ruell), an even nerdier fellow with a nasal voice and no apparent interests beyond exchanging chat room messages with a distant girl. When grandma is injured in a dune buggy crash, the brothers find themselves temporarily in the dubious care of Uncle Rico (Jon Gries), a hopeless dreamer obsessed with his high school football days–the high point in his life–who’s trying to begin a career as a door-to-door salesman of, among other things, breast enhancement products. What little plot there is centers on Napoleon’s effort to help his new friend Pedro (Efren Ramirez), the sole Latino in the school, get elected as class president against a popular member of the “in” crowd, and his goofy romancing of Deb (Tina Majorino), a girl almost as isolated as he is. Kip’s long-distance sweetheart also turns up in the form of Lafawnduh (Shondrella Avery), a Detroit diva under whose tutelage the guy is transformed into something like Jerry Lewis’ version of an inner-city thug.

Nothing makes much sense in “Napoleon Dynamite,” of course, because the picture is basically just a succession of ain’t-these-hicks-dumb gags that, despite the deadpan tone, just keep escalating in absurdity. The sheer madness of the goings-on occasionally gets so surrealistically outrageous that you’ll surely crack a smile, but the laughter will be at the expense of the characters rather than with them; they’re all just convenient comic punching bags, without the slightest hint of the endearing about them. The attitude that pervades the picture is cruel and mean-spirited, in its own way as taunting as that of the bullies who make Napoleon’s life miserable; viewers are basically invited to watch these dumb-as-a-post characters make fools of themselves for ninety minutes and thereby feel wonderfully superior. (The exception, of course, is Lafawnduh, who as a modern black woman might be as much a caricature as anybody else but must nonetheless be portrayed as knowing, ultra-smooth and absolutely self-confident. Pedro, on the other hand, is depicted as a near-catatonic cipher.)

Within this context you have to give credit to the cast for doing what’s demanded of them–particularly Heder, who certainly succeeds in appearing the ultimate geek. (One hopes that’s the result of acting, not merely playing himself.) Technically the movie is ragged and gritty, in the fashion of bargain-basement independent flicks, but appearance is the least of its problems. “Napoleon Dynamite” is the sort of nasty conceit that might have worked in the original short-film form, but in this elongated feature format, it quickly deflates, becoming in the end about as exciting as a game of the title character’s sport of choice–tetherball.