You've got to give British filmmaker Danny Boyle credit. Following on the heels of his independent film hits "Shallow Grave" and "Trainspotting," the last thing you'd expect him to make is a romantic comedy set in the United States.

And that's definitely what "A Life Less Ordinary" turns out to be (at least for the most part), although the situations are handled in Boyle's customarily quirky manner. Frankly, it probably wasn't a risk that was worth taking.

For an hour it appears that he and screenwriter John Hodge have actually pulled off the feat, as the film's screwball first half is very funny. However, things really bog down in the film's final 45 minutes, when the action becomes far too violent and serious.

In fact, the whole movie is a bit muddled, as it mixes some seemingly disparate elements — romance, adventure, action and angelic intervention.

The aforementioned angels are O'Reilly (Holly Hunter) and Jackson (Delroy Lindo), who are given the difficult assignment of bringing together failed-author-turned-unemployed-janitor Robert (Ewan McGregor) and spoiled rich girl Celine (Cameron Diaz).

The two should-be lovers meet when Robert forcibly asks his boss, Naville (Ian Holm), for his job back. During a scuffle with Naville's bodyguards, he winds up abducting the millionaire's daughter Celine at gunpoint.

But Robert isn't exactly a great or well-organized kidnapper, and Celine actually begins to plan the caper for him. In the meantime, Naville has sent a pair of bounty hunters after Robert, O'Reilly and Jackson in human guise.

Boyle's obvious inspiration here is some of Frank Capra's films, including the screwball classic "It Happened One Night." But there's an unfortunate tendency toward "modern" storytelling techniques that sabotage some very promising scenes.

Most annoying of all is the goofy, "earthy" angel bit, a silly conceit that never quite works. It's not all that funny and seems to exist solely for shock value or to provide irreverence.

As for the performances, McGregor is extremely charming, while Diaz takes a while to "find" her character. And while Hunter is so weird she's almost hilarious, Lindo has to play the bland straight man to her antics.

Similarly wasted in supporting roles are character actors Stanley Tucci, Tony Shalhoub and Dan Hedaya, who plays the angel Gabriel as police chief.

It is worth noting that most of the film's scenes were shot in Utah, and some feature familiar locations (the Copper Pit Saloon and Deer Valley Resort are both featured prominently).

"A Life Less Ordinary" is rated R for violence, some foul language, brief gore and a few vulgar references and jokes.