Starring: Owen Wilson, Vince Vaughn, Rachel McAdams, Christopher Walken

6 out of 10 stars

The manic and sometimes inspired Wedding Crashers is buoyed by some of the most raunchy, offensive, and hilarious jokes to be seen in a mainstream comedy in a while - which is good, because this movie needs all the help it can get. Otherwise just a sappy romantic comedy with the standard misunderstandings and wacky set-pieces, Wedding Crashers takes on a fervent, wild-eyed life of its own when it allows its stars, Owen Wilson and Vince Vaughn, to let loose with words, thoughts, and deeds that leave the pristine territory of the PG-13 rating far behind. Not that anything Wilson and Vaughn do is totally out of control or unredeemable - the few instances of such are left to their co-stars - but it certainly crosses a line we haven't seen in a while, that of adult humor. Not "adult" as in "mature, thoughtful, meaningful" but rather in a more Playboy magazine style. Puritans might call it smut, but with nary a thought in its gleefully empty head, Wedding Crashers is just smut-lite, minus most of the grime. Though it loves having dirty thoughts, this is one movie that won't make you feel as if you need a shower when it's over.

What you will need is a stimulant of some kind, because after it exhausts its limited repertoire of sex jokes, Wedding Crashers crashes like a college kid after a vigorous all-nighter. What's even more distressing is that the movie doesn't even just crash and burn, but limps into such a standard, predictable, formulaic third act that you could leave during the beginning of a scene and return at the end knowing exactly where you are, and exactly where you're headed. It's truly disappointing because, for a while there, you might feel you are in the presence of something resembling greatness, or at least its two stars at the height of their comic powers.

John Beckwith (Wilson) and Jeremy Klein (Vaughn) are two men whose lives are steeped in marriage - not to wives, or to each other, but to the institution itself. During the week they're divorce mediators, shepherding bickering couples through acrimonious settlements of who gets the frequent flier miles and to whom exactly do the golf clubs belong; on weekends, they're wedding crashers extraordinaire, mapping out plans of attack that would put most generals to shame. Whether the bride and groom are Jewish, Indian, Irish, Chinese, or just plain boring, John and Jeremy have a way of making themselves the lives of the party, and with their outrageous made-up personas, they attract the attention of comely single women who, turned on by the wedding shenanigans, are ready to boink any sensitive male that gets teary-eyed during a ceremony. It's a wild, wild life of wine, women and fun, and it looks like the current season has drawn to a close until Jeremy finds what might be the great white whale of weddings, that of the daughter of the Secretary of the Treasury, William Cleary (Christopher Walken), one festooned with VIPs and Secret Service. Turned on by the thrill of pulling the caper off, John and Jeremy stoop to conquer - that is, until John spies lovely maid of honor Claire (Rachel McAdams) and suddenly finds he has a heart in the spot where he thought he housed his libido.

The first part of Wedding Crashers - basically an extended montage of John and Jeremy's wedding antics - starts things off on a brisk, fun note; the energy and byplay between the two stars is fast and furious and very, very fun. It's not so much the cleverness of the one-liners that works as it is the rat-a-tat-tat delivery and spontaneous feel Vaughn and Wilson give them. In a short period of time they manage to win you over, and by the time the Cleary wedding starts, they've got you in the palms of their sweaty hands. And it's at this wedding where things go from just kind of smutty and sleazy and rocket off into the bizarro stratosphere. The initial flirting between Claire and John is charming if rote (Wilson and McAdams do have genuine chemistry), and Jeremy's seduction of whacko bridesmaid Gloria (Isla Fisher) is a nice variation on his previous conquests. However, it's when John decides to pursue Claire further that things get out of hand, as he wangles an invite to her family weekend gathering - and what do you know, Gloria's her sister, so Jeremy can come along!

To say hijinks ensue is a bit of an understatement. There's the foul-mouthed grandmother, the drunken nympho mom (Jane Seymour, brilliantly cast), a band of ferocious frat boys including Claire's boyfriend (Bradley Cooper, all cartoon menace), the "artistic" outcast brother, and of course, the Cleary patriarch, whom Walken instills with a quietly offbeat stillness that hints at murky, disturbing depths. Most of these characters, though, are just foils for Vaughn and Wilson, who give 110% (if not more) to standard set-ups like a ferocious touch football game or a quail hunting expedition. The movie tips over into Porky's territory more than once, with the manic Fisher manually stimulating Vaughn at the dinner table and then later tying him to his bed, but it moves at such a rapid pace that plausibility no longer becomes a factor and outrageousness becomes the norm.

Sadly, it all falls down with a loud thud a little over the halfway mark, and the previous crazy humor is chucked out the window for scenes of moping and reconciliation. Even Vaughn and Wilson seem to have the wind taken out of their sails; only McAdams, who's charming from the instant she appears on the screen, manages to carry her scenes with anything resembling energy. As the calm center in the Cleary family storm, she gives the movie's one true, heartfelt performance, an accomplishment that's made even more amazing by the fact that Wilson seems to be performing a strange stand-up version of his character, and not actually acting. Not that that's bad - when both Wilson and Vaughn are on, they're great, and Vaughn in particular is incredibly fearless when it comes to anything thrown at him. But the first, wonderful half and the second, damp half of the movie don't mesh at all, a fact made all the worse by one of the most soul-deadening cameos in recent memory (hint: it's a comic actor you've already seen way too much of this year). When this character shows up, you know that the party's not just over, it's officially dead.