James Rampton meets Rufus Sewell, who insists he's not really moody
Rufus Sewell's family motto must be "I smoulder, therefore I am". Journalists drool over Mr Pouty, Mr Broody, Mr Achingly Handsome, even Mr Lustbox. The epithet "Byronic" has pursued him like an especially diligent autograph-hunter.

In person, Sewell does not disappoint. Not to be outdone by those other writers, I have to report that he is unfeasibly gorgeous. Under a lava- flow of dark curls, his green eyes twinkle like an over-active Tinkerbell and his cheekbones appear to be hewn from granite. It is easy to see why the tabloids have tried so hard to link him with other iconic beauties such as Madonna, Kate Winslet, Patsy Kensit and Emma Thompson.

Sewell laughs off his sex-symbol label. "As a human being, I like it, but as an actor, it's silly. Normally, I smoulder when I can't think what to do. When you play a bus-driver (as he did in A Man of No Importance), and you still get called Byronic, you think, 'what have I got to do to get away from this?'."

He also dismisses his reputation for moody, wordless communication. "When I used to chat up girls, I'd convey a lot across a room, but as soon as I opened my mouth, I'd ruin it all by saying something stupid. It's not something you can practise - 'you can't speak to Rufus, he's practising conveying things without speaking'."

That is not the only way Sewell has been pigeonholed. After acclaimed performances in Middlemarch, Cold Comfort Farm, Carrington and The Woodlanders, he was typecast as the 'Prince of Period', unimaginable in anything but a frock-coat, frilly-shirt and riding boots.

Sewell admits that, particularly in the wake of his swoon-inducing role as Will Ladislaw in Middlemarch, he "could have had a career that blossomed in the direction of 'Quality-Street-long-coat-curly-hair' acting. I had to exercise restraint. You can do fifteen films and one Yorkie ad, and if the ad is successful, then you become "the Yorkie boy". There was a touch of that going on. Now I have no interest in romantic leads - that's the boring stuff. At drama school, I was a comic actor."

In an attempt to get back to those roots, Sewell has binned the period breeches in favour of a pair of shabby jeans for his latest role. In Martha - Meet Frank, Daniel and Laurence, a British comedy already being given the inevitable (and unenviable) tag of "the new Four Weddings and a Funeral", he plays Frank, a hard-drinking former child-star actor who has been "resting" for more years than he'd care to recall. Filled with self-loathing, he gets piles of fan mail from six-year-old girls when his old films are on television every other Christmas. To fuel his sense of failure, occasionally they run 'whatever happened to ...?' columns about him.

"Frank is someone who was quite famous when he was nine years old, and has grown up into someone slightly wonky," Sewell explains. "He hasn't worked since he was about 15. He drinks a lot, smokes a lot, is very cynical, sarcastic and full of self-pity."

Over one weekend, Frank and bickering childhood friends - the arrogant Daniel (Tom Hollander), and more gentle Laurence (Joseph Fiennes) - are all smitten with American woman, Martha (Monica Potter).

"When I left drama school, I was careful not to get stuck in comedy," Sewell recalls. "But I wanted to smoke cigarettes and swear a lot, so this part is perfect. I've read a lot of romantic comedy scripts in the past few years. Normally you just wait for the Wet Wet Wet song at the end. But this one's got bite."

For all its edge, the film offers Sewell the rare chance to slough off the brooding image and flourish his natural sense of humour. "Sometimes good-looking men suffer like good-looking women do - people think they can't do anything other than be good-looking," says Nick Hamm, director of Martha - Meet Frank, Daniel and Laurence. "But Rufus is a very funny man. He likes taking the piss out of himself. Now he's finally been given the chance. All actors love playing failed actors. They can get out all that horrible stuff they have experienced. His is a great performance as the "Withnail of the Nineties"."

Hamm may be partisan, but Sewell is certainly "hot" at the moment. With two recent US hits (Dangerous Beauty, with Catherine McCormack, and Dark City) and two more in the pipeline (At Satchem Farm, with Minnie Driver, and John Turturro's Illuminata), he is in the vanguard of the "Brit-hip" invasion of Hollywood. A three-picture deal has already been dangled in front of him.

"I've been offered Schwarzenegger-type blockbusters, but I wouldn't be any good in them. If you're second-rate in a second-rate blockbuster, you lose out."

The 31-year-old Sewell can be choosy. "If it's stock romantic heroes out of fifth-rate, tuppenny novels, I'm not interested," he declares. "But a year's unemployment and I might go back to them."

I doubt that will be necessary.

Martha - Meet Frank, Daniel and Laurence opens today.