Rob Schneider's new low-brow body-swap romp "The Hot Chick" is such an insipidly sexist so-called comedy that the movie's entire female cast is reduced to jumping up and down, giggling and playing patty-cake while rhyming about the ickiness of sex.

These characters don't have a brain cell to share among them, but Schneider (who plays an idiot too, but what else is new?) and director Tom Brady genuinely expect the audience to identify with these one-dimensional teenage airheads.

More specifically, they expect us to identify with catty queen ditz Jessica (Rachel McAdams), who, through a curse not worth explaining here, wakes up in the short, hairy, burlap-sack body of a scummy, gas-station-robbing low-life (Schneider) just a few days before the prom.

As the transformed Jessica, Schnieder bounces around with limp wrists, wearing tight tummy tops and hip huggers, twirling his hair on his finger and assuming that's enough to sustain laughs for the length of the movie. Meanwhile he -- I mean she -- and her posse of puerile girlfriends (lead by Anna Feris, "Scary Movie 1" and "2") have sleepovers and makeovers during their quest for a way to break the curse.

Dumb, flat and full of insultingly obvious holes, the minimal-effort plot finds Jessica/Schneider posing as a Mexican gardener to have a male-bonding moment with her father and as a school janitor for no reason whatsoever. When the prom rolls around and she's still stuck in Schneider's body, Jessica takes Feris to the dance so she can keep an eye on her boyfriend (Andrew Keegan). But because it's not part of the paltry script, no one there even notices that the second most popular girl in school seems to be dating the janitor.

There is one great performance in "The Hot Chick," but it's been largely excised -- probably because Schneider was being badly upstaged. Pretty, dainty McAdams, who plays Jessica before the switcheroo, had several scenes in an early cut of the film featuring her misadventures as Schneider's cretin character in a girl's body, grunting, cursing, drinking, stumbling in high heels, shoplifting, becoming a stripper and beating up guys who come on to her.

In the version of the "The Hot Chick" released in theaters, however, McAdams has only two such scenes left. But she's so much funnier than anything or anyone else around her that there's a temptation to ponder the possibilities if the picture had aimed higher than just being another half-assed vehicle for a one-note "Saturday Night Live" alum.