RV

Reminiscent of Chevy Chase's 1980s "National Lampoon's Vacation" comedies, "RV" stars Robin Williams as a distressed husband and father who practices family togetherness on a road trip to the Colorado Rockies.

The result is a predictable mixture of slapstick, sappiness and opportunities for Williams to do stand-up schtick. He leaps at the chance to create improvised monologues, which are (no surprise) wittier than anything else in the script. Unfortunately, he shows just as much enthusiasm for the drippy filler that gums up the movie's final half hour.

Williams plays Bob Munro, a workaholic genius who can smooth-talk his way through any business crisis. His cranky wife, Jamie (Cheryl Hines), and their alienated kids, 15-year-old Cassie (Joanna "JoJo" Levesque) and 12-year-old Carl (Josh Hutcherson), had been planning on a Hawaiian vacation, but Bob abruptly informs them that's not happening.

He's in trouble at work, thanks mostly to Cassie's politically correct best friend, who insults Bob's obnoxious boss Todd (Will Arnett) at a party. Todd, who fears losing face at work, considers firing Bob but offers him a way out: If he can make a crucial presentation in Colorado, he can keep his job.

Taking to the road in a monstrous RV that extends for most of one city block, the Munros are befriended by another trailer-park family, the relentlessly chipper Gornickes, whose patriarch (the perfectly cast Jeff Daniels) admits that "we ain't everybody's cup of sunshine."

Indeed, the Munros are so horrified by the Gornickes' nonstop glee and RV lifestyle that they flee from them at every opportunity. "Try to remember, we're not friendly," says Jamie. But the chemistry between the Gornicke teenagers and the Munro kids cannot be denied, and eventually Bob and Jamie cave in as well.

Trouble is, the Gornickes are so sweet and generous that they make the Munros look like selfish snobs. The movie leaves you wanting to spend more time with the former and less with the latter. As the fearless Arnett plays him, even the treacherous Todd is more interesting than the Munros, who come off as standard-issue dysfunctional types.

When it's time for them to kiss and make up, you don't believe a single contrived reconciliation scene. The script is by Geoff Rodkey, who wrote Eddie Murphy's "Daddy Day Care" and recently worked on the convictionless remake of "The Shaggy Dog."

For choosing Daniels and letting Williams go to town with his monologues, credit the director, Barry Sonnenfeld, who made "Get Shorty" and the "Addams Family" movies and once seemed headed for a brilliant career. That came to an abrupt halt four years ago with the nearly simultaneous release of Tim Allen's "Big Trouble" and the unnecessary "Men in Black II."

He's been busiest lately as a producer ("Lemony Snicket's A Series of Unfortunate Events," "The Ladykillers"). Once a cinematographer, he gives "RV" a visual distinction that it otherwise might have lacked. He makes the most of the gorgeous Alberta locations as well as the scenery-obliterating nature of that big bus.

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