One hungers for fame and the other one's along for the ride

It's probably fitting that portions of the new Farrelly Brothers' chewy but minor comedy, Stuck on You, are set during the winter in a resort town -- Martha's Vineyard -- like their first picture out of the toboggan chute, Dumb and Dumber. Both movies seem to come out of a taste-free zone partially inspired by Rankin/Bass, the animation studio responsible for the holiday stop-motion, self-pity classics like Rudolph the Red-Nosed Reindeer.

Bobby and Peter Farrelly's creations -- this time it's the conjoined 32-year-old twins Bob and Walt Tenor -- reside happily in a landscape like the Island of Misfit Toys. For the Tenor boys, it's the small town where they run a thriving diner, Quickee Burger, in which they guarantee to get the food to the table in three minutes, no matter how big the order.

With Stuck on You, which opens nationwide today, the Farrelly Brothers have a big, steaming order to deliver. They must compete with the legacy of their own bad taste, for which they compensate with a quality that some may find even more repellent -- sentimentality. It's a much funnier movie than the trailer would lead you to believe; it would almost have to be. But it is just not as consistent as their previous trash wallows.

Bob (Matt Damon) and Walt (Greg Kinnear) are country mouse and city mouse who are actually joined at the hip; the directors bring the double-sided motif closer together than ever before. Bob is happy slinging burgers, while Walt aspires to be an actor -- a successful one, that is. He's already the biggest thing in their hometown, where he stars as Truman Capote in the one-man show "Tru."

Some of the funniest stuff in the movie involves the comparison of Robert Morse's version to Walt's. It's a little more amusing than Bob's having a panic attack at the prospect of having to be onstage, though badly hidden, with his brother. Yet Walt is the kind of ambitious comet who might be played by Morse -- he's an audacious operator who's gifted at charming everyone.

While Walt succeeds without really trying, Bob hides under his bangs and maintains an e-mail relationship with a girl he's been writing to for three years but hasn't met. When Walt decides it's time for the brothers to move to Hollywood -- "I think I got the chops," he says of his motivation, an utterly absurd situation that's treated seriously -- he convinces his younger brother by saying it's a chance for Bob to see his Internet honey, May Fong (Wen Yann Shih), in person.

Walt has less of their liver than Bob -- it's how the movie explains why a separation surgery would be risky, since there's only a 50-50 chance that Walt would survive. (It's also the excuse for Walt looking older; Kinnear is seven years Damon's senior, but that doesn't explain why he seems to be wearing Jeff Daniels's hair from Dumb and Dumber.)

But after 32 years the Tenors have become a marvelously functioning machine by necessity and because of affection. (We get a flashback of their athletic achievements that includes a cameo by the Dolphins running back Ricky Williams as their high school football coach.)

Walt's gargantuan optimism gives the movie a soul; it needs one since it barely has a look. The scenes set in the Hollywood residential hotel where they live look even faker than Walt's hair. On the other hand, the twins' relocation to Los Angeles gives the Farrellys a chance for the most glamorous shot of their careers, a camera move that starts with a palm-frond-view of Hollywood Boulevard and descends to the street.