The Perfect Charmer   Being mean and moody is all an act for Colin Firth   This can't really be Colin Firth sitting in front of me. Colin Firth is brooding and unsmiling, with a tendency towards the morose. Or so I had been told. So who is this charming man? Amiable and polite, he's nodding greetings and exchanging warm handshakes as he comes into the room before easing himself into a chair. That's the confusion between the public and the private as far as Firth is concerned. To millions of women all over the world, his roles in Pride and Prejudice and Bridget Jones's Diary have fostered the image of an emotionally constipated sort of man who just needs mothering.

Yet in the semi-public role of press interviews, Firth seems sufficiently relaxed to convince you that the private Firth is probably someone whose company is sought out by his friends ... a man worlds apart from Jane Austen's Mr Gloomy, Gus Darcy.

Firth is the first to acknowledge that there is a public perception of "the Colin Firth type". Even his friends are aware of it.

Hope Springs came recommended to him when it was in novel form—it was then called New Cardiff and attracted attention as Charles Webb's second novel after The Graduate. Two different friends on separate occasions each told Colin that the lead role had his name on it.

Firth sought out the book, read it, and agreed. By further coincidence, the man who had the film rights to the book also happened to be the producer of the film he was working on at the time, leaving him well placed "to make a pest of myself" as he puts it.

"I think the 'Colin Firth character' is probably more easily identified by other people than by me," he agrees. "I usually   find that when I get asked questions it's generally about some assumption they have about the type of character that I've been playing.'

In an interview just a few minutes earlier, he'd been told he always played "someone who's attracted to a woman". He smiles at the thought of what else anyone might assume he would be attracted to.

There are two schools of thought about acting. One holds that it is essentially a process of transformation while the other suggests that the characters you play are an extension of the yourself.

After some thought, Firth tends to agree with the autobiographical theory.

"I think like most creative pursuits you are drawing on aspects of yourself," he says.

"I think that acting is particular in that there is an emphasis in peoples' minds on changeability and versatility, because acting is perceived to be the art of transforming yourself.

"I actually don't see it like that, although I have made attempts at transformation—quite wild attempts sometimes," he adds with a smile, "with greater or lesser success. I do find it quite a fun exercise, but it's not the principally interesting thing for me."

One of those transformations is in Hope Springs, where he has to play an artist. He was required to do it again in his current film, The Girl With a Pearl Earring, in which he plays the artist Vermeer.

"I have no artistic talent whatsoever," he points out quickly. "It basically took hours of lessons to look like I'm someone who wouldn't drop his paintbrush."

For Firth, the trick is to take whatever he can bring to a situation and apply it to the problems of the plot. He's much more interested in working out what he would do in a situation, rather than what his character would do.

"I saw an interview," he digresses, "with another actor who was being asked this sort of question, along similar lines. He pointed out that probably most actors—with a couple of very notable exceptions—are pretty sameish in most of what they do."

It's true inasmuch as actors such as George Clooney, Julia Roberts and—closer to home—Hugh Grant have been very successful by essentially being themselves. There's nothing wrong with that as far as Colin Firth is concerned, but for him it's the story which interests him.

In the case of Hope Springs, he plays a British artist who pitches up in the eponymous small town in New England. He is trying to escape in the belief that his fiancee, Minnie Driver, has dumped him.

After seeking solace in the arms of local ditz Heather Graham he is horrified when Driver turns up insisting it has all been a mistake.

The notion of an Englishman adrift in the US is one to which Firth could easily relate.

He has had "a very long relationship" with America. For one thing, his 12-year-old son, Will, lives there with his mother, the actress Meg Tilly. Firth has another son, two-year-old Luca, who lives with him and his wife in Italy.

Firth's own mother, an Open University lecturer, spent a large part of her childhood in the US and Firth also went to school there for a little while. This was part of a nomadic childhood, which also took him to Nigeria.

"Actually," he says of his trans-Atlantic crossings, "I was nicknamed 'The Yank' for years when I first came back from America and then into my teens."

The nickname came from the American accent and mannerisms he had acquired—"I was very feeble minded that way".

"I'd been going from school to school and it had been astonishing to me that at my first ever school these kids did not talk like my parents did," he recalls. "They spoke with a BBC, received pronunciation sound and there I was in a state school in Essex," he shrugs.

"That was a culture shock that I had to deal with, and just when I thought I'd mastered Essex and the Billericay tones I was in a Hampshire school. And then America. So," he adds wryly, "strangely enough I became an actor."

Firth does not appear to be as emotionally needy as most actors. Perhaps that wandering childhood produced a self- reliance. Whatever the reason he craves solitude the way others crave the roar of the crowd.

Hope Springs was filmed in a small town near Vancouver. It was quiet, it was isolated, it was peaceful and Firth could not have been happier.

"I have felt tempted to escape and hide away in a place like Hope Springs," he says. "I sort of lived for five years near the place where we shot the film. It was five years in a log cabin really. I did work and I came back—so I wasn't totally escaping from it—but I do have that tendency to find a retreat."

That tendency may be something he will have to curb in the near future. Firth insists he doesn't have much of a profile in the US. The Pride and Prejudice wet shirt phenomenon did not cross the Atlantic it seems.

"It did well in the States," he agrees. "It broke records for that particular television company, but that doesn't get it on the map the way it did here.

"I don't think it became the talking point, there are so many options on television in America and I think that costume dramas from Britain would be far more marginalised.

"Here, there was a great deal of focus on it, it got talked about on discussion shows, and it became a bit like the World Cup. I'm not sure how it works over there, but I think programmes like 24 probably were more of a nationwide phenomenon."

Firth maintains he can walk down the street in America without being recognised, but I would hazard a guess at those days being numbered.

Bridget Jones's Diary was a solid success and his new film, What A Girl Wants, has been in the US top ten for four weeks. With Hope Springs still to be released and his next film Love Actually being tipped to do Notting Hill-type business, Colin can probably count the remaining days of his anonymity on one hand.

If he does become a household name in America, then that tendency for solitude may have to be curbed. But I wouldn't bet on it.