It's difficult to imagine a more thoroughly unpleasant experience than sitting through "Just Married," an abrasive, unsavory assault on the senses starring Brittany Murphy and Ashton Kutcher.

Remember those names, if only for the purpose of reminding yourself of what passed for the Next Big Things in 2003. Actually, Murphy probably has a future if she manages to avoid material like this, but Kutcher -- who was the star of a television sitcom called "That '70s Show" -- is a performer best suited to the small screen. The smaller the better, in fact.

Here, Murphy and Kutcher play Sarah McNerney and Tom Leezak, two carefree young people who meet on a beach in Los Angeles, fall into bed that night, set up housekeeping a few weeks later and get married a few weeks after that. (Who said Hollywood doesn't believe in family values?) "Just Married" has to do mostly with their European honeymoon, during which nearly everything that could go wrong does, a phenomenon that in this case might appropriately be called Brittany's Law. Bloody noses, head-butts, a teensy weensy rental car, a near-electrocution while plugging in a sexual aid, a flatulent innkeeper, a huge cockroach, a half-dressed chase through a Venice hotel, a rectal search at an Italian airport -- each gets the same goofy giggle from Murphy and mock-infuriated head shake from Kutcher. "Just Married" is a veritable orgy of strained physical gags, inane vulgarity and poor comic timing. You know a movie is in trouble when its biggest laughs come not from its lead players but from a dog and a car.

Kutcher and Murphy are a real-life couple, but one would never know it from "Just Married," which in an hour and a half fails to spark any chemistry whatsoever between its protagonists. It's particularly painful to watch Murphy -- who was so perfectly cast as the love interest in "8 Mile" -- try to be Reese Witherspoon, when her flashing eyes and dangerous, just-kissed pout clearly indicate that her true calling is that of a bad girl, with or without a heart of gold. Unremarkably directed by Shawn Levy ("Big Fat Liar") from an execrable script by Sam Harper, "Just Married" is the kind of movie whose existence is completely unjustified save for the two careers it's supposed to ignite. Whether audiences comply is their business, but with so many terrific movies out right now, they can surely find something better to do with their time than serve as human jumper cables.

Just Married (95 minutes, at area theaters) is rated PG-13 for sexual content, crude humor and a brief drug reference.

Ashton Kutcher and Brittany Murphy with a real dog in "Just Married."