Film: * ½

Diaz: * * *

Cameron Diaz, Ashton Kutcher, Lake Bell, Rob Corddry, Queen Latifah, Treat Williams, Dennis Farina, Dennis Miller. Written by Dana Fox. Directed by Tom Vaughan. Rated PG-13. 99 minutes. 20th Century Fox.

As lowbrow comedies go, What Happens in Vegas is neck and neck at the limbo stick with Made of Honor and Fool’s Gold for the most insipid American romantic comedy of the year. The new Cameron Diaz-Ashton Kutcher vehicle about a down-on-their-luck pair who hit a the jackpot after a regrettable quickie wedding, is for most of its running time, juvenile, slapstick and embarrassing.

However, What Happens in Vegas, with its adolescent depth and stupidity on its sleeve, should sit well with its target audience, who these days demand neither the romantic nor the comedic in a romantic comedy.

When high-maintenance Manhattan career girl Joy (Diaz) gets dumped instead of engaged, she tailspins all the way to Vegas to drown her sorrows with best gal Tipper (Lake Bell). At the same time, slack Brooklyn carpenter Jack (Kutcher) gets axed from the family business by his father (Treat Williams), grabbing his sardonic bud “Hater” (Rob Corddry) and heading to—you guessed it—Sin City (apparently where you go when you lose your job and have no money).

A meet-cute contrivance lands both couples in the same hotel and room, in a scene that is crawl-under-the-seat not funny and pushed to slapstick extremes with actors screaming and tackling each other in what could have been worked out in two sentences.

Rebounding, opposites Joy and Jack inadvertently get wasted (cue more bad and broad physical shenanigans and music) and wake up the next morning to shame at the buffet—hitched. Anyone who has seen the trailer knows what happens next—Joy’s quarter scores $3 million in a slot pulled by Jack. Big problems ensue.

Back in New York, an irritable judge (Dennis Miller) takes one look at the shallow two-some and freezes the cash, sentencing them to six months “hard marriage” that sets the film up for an odd-couple living arrangement including trips to a marriage counselor (Queen Latifah) and strategies with their respective pals designed to get the other to forfeit half of the take before the six months are up.

The film revels in adults behaving like fools, not unlike the wretched Made of Honor but a tad more fun since both stars display humor even while throwing fruit at each other in crowded streets, bickering, urinating in kitchen sinks, bickering, removing toilet seats, bickering—you get the point. This goes on and on, about one-tenth as funny as it should be, until the film decides to settle down near the end and it actually becomes watchable though anyone over 10 knows exactly where it is going.

Diaz is immensely likable as always and that takes her empty character a long way, but by now she can auto-pilot through a movie like this with her eyes closed. She’s still the loveliest blonde in movies this side of Michelle Pfeiffer, and her signature daffy sense of humor is firmly intact here though it’s starting to become schtick.

It’s time for Diaz to put fluff like this to rest. At 35 and with impressive past dramatic turns in films like Gangs of New York and Things You Can Tell Just by Looking at Her, the actress who went gritty over a decade ago in Feeling Minnesota must now walk away from bubbly nonsense like What Happens in Vegas, or become the next Matthew McConaughey.

Kutcher isn’t remotely believable as a blue-collar New Yorker, looking impossibly handsome here and more like a scrubbed A&F model than a fledgling carpenter and crass layabout. When he cleans up in the film’s final third, he turns on the charisma and Jack suddenly becomes a nice guy, giving him a chance to calm down for the first time onscreen today, and it suits him.

The pair really click in the film’s last third, which is much too little, and much too late for What Happens in Vegas. By the time Dennis Farina shows up and Joy’s pushy boss, forced several times to make a painfully unfunny joke about Jack’s name, and the two begin to relate as semi-real people during the oddest use of the song “Flashdance” that I’ve ever seen, the film gets a lift even it loses points for predictability in a hokey but nice final scene.

One has to feel sorry for both talented Diaz and Kutcher, as well as the state of the modern American comedy. Sitting together in a two-shot at a lawn party late in the film, they are every inch movie stars, stuck in one sorry sitcom. What Happens in Vegas is 2/3 yuck, 1/3 sweet and all cliché.

- Lee Shoquist

lee@atnzone.com