The film: It's possible that Ashton Kutcher and Cameron Diaz got together during the read-through stages of this production and decided the only way to deal with this pile of rubbish was to yell as often as they could, thereby hoping no one would listen to the drivel coming out of their mouths. But that's probably being too kind.

What scares most about What Happens in Vegas is you're left with the conclusion the cast actually think it's funny. There's a smarmy smugness to the whole affair that says, 'hey, look at how wild and wacky we are'. You'll be grinding your teeth within minutes.

The basic premise, in more capable hands than Tom Vaughn's, might have landed some blows on the face of modern social conventions. There's certainly nothing new about it - warring 'couple', thrown together by circumstance, must learn to live together - but they may have played it all off against the temptations of Vegas and perhaps even thought about having the two stars play against type. To borrow a phrase from the city where it's set, no dice.

Diaz (right with Kutcher) plays the lovable goof who - for reasons known only in the heavens - no one up until this point actually does love, while Kutcher plays the obnoxious loudmouth that everyone somehow finds funny, even when he's not. Painfully not.

They are both dumped by their partners, head to Vegas to ease the pain and find themselves in adjoining rooms. One wild night later, they find themselves hitched. And just when they decide it was all a big mistake, fate - or a large poker machine - intervenes and they are forced to sweat it out before they can collect the cash.

Cue a series of scenes where they fight, yell, run around and yell some more. The only achievement you are left crediting the director for is he has somehow been able to make Diaz thoroughly unattractive.

Kutcher, well, he's fast outstaying his welcome.

You know you're in trouble when they name a character Dick Banger, and then whop you over the head with the fact about a dozen times. Gross-out, obnoxious comedy can work - it harks back to the days of Animal House, after all - but you've got to have a sense of smarts. And show a little heart.

The extras: The director and his editor try valiantly on the commentary track - but you might take some convincing. The featurettes won't help if you're annoyed either - they include the two stars talking about the opposite sex and Corddry getting more air-time in character. There's also a gag reel that at least shows the cast were enjoying themselves. At times.

The verdict: Loud, obnoxious and utterly unfunny.