Role of a lifetime suits Colin Firth

It's hard to believe, seeing him looking resplendent in an immaculately tailored suit and elegant, open-necked shirt, that Colin Firth says he is in the tradition of actors who do not dress well and who prefer T-shirts to tuxes.

Then why the fashion-plate looks? "I'm dressed nicely today because this is a Tom Ford moment," he laughed. "It helps if you get Tom Ford to dress you."

Ford, the fashion designer who was the creative director at Gucci for 10 years, has directed his first film, the beautifully photographed A Single Man, based on his adaptation of the Christopher Isherwood novel. The movie, which had its premiere at the Toronto International Film Festival, opens Dec. 11.

Set in 1962 in Los Angeles, it stars 49-year-old Firth as George Falconer, a British college professor who is struggling to find meaning to his life after the death in a car crash of his longtime partner Jim (Matthew Goode).

The film follows George through a single day in which he puts his affairs in order and meticulously rehearses his own suicide but has trouble finding a practical or aesthetically pleasing way of carrying it off. During the day he meets with colleagues, talks with a student who has a crush on him and has dinner with an old friend, played by Julianne Moore.

Described as the role of a lifetime, it won the Best Actor prize for Firth at the Venice Film Festival and there is Oscar talk about his performance. Ford, who financed his first feature himself, sparked the British actor's interest by bypassing agents to contact him.

"He just sent me an email," recalled Firth. "I'd never given him my address, but I was struck by the eloquence and sensitivity of what he wrote. Also the choice of material interested me because it wasn't what I expected. I mean, if one lazily thinks of what a fashion designer might do if he's going to conquer cinema next it would be taking the opportunity to display his fashion sensibilities. Choosing the life of a lonely professor in despair in 1962 doesn't really seem like an opportunity to show your spring collection."

Firth made enquiries and discovered people took both Ford and the project seriously. Once he agreed to sign on, things moved quickly. There was no rehearsal and very little preparation. Firth arrived in Los Angeles on a Saturday, was on the set the following Monday and Ford shot the film in a brisk 21 days.

"The script was quite sparse and it left a lot of space," said Firth. "Tom didn't tell me how to do anything and didn't bombard us with verbal instructions. He gave us a lot of freedom and I felt I was being given a chance to do things I wasn't normally given a chance to do."

Firth, who has enjoyed successful runs on the London stage and solidly reliable screen performances as varied as Mr. Darcy in TV's Pride and Prejudice, Mark Darcy in Bridget Jones's Diary and Harry in Mamma Mia! was talking in the Beverly Wilshire Hotel in Los Angeles.

Later that day, he was to receive BAFTA/L.A.'s Humanitarian Award for his work in helping to fight poverty and injustice around the world and particularly in Africa. A dedicated supporter of Oxfam International, he was named Philanthropist of the Year last year by the Hollywood Reporter, the film industry newspaper, and in 2006 he was voted European Campaigner of the Year by the European Union.

He brushes it aside, saying: "My parents and grandparents have always been engaged in teaching or the medical profession or the priesthood so I've sort of grown up with a sense of complicity in the lives of other people, so there's no virtue in that; it's the way one is raised. But I'm just a kind of medium. The people who do the real work don't get heard."

Born in Nigeria, the son of academic lecturers, Firth settled in England with his family when he was 4 years old. He studied at the National Youth Theatre and, at the age of 23, was cast as the lead in a West End production of Another Country.

He had his first starring film role in 1989 in Milos Forman's Valmont and then moved to British Columbia briefly, living with Canadian actress Meg Tilly, who he met on the Valmont set and with whom he has a son, Will.

Although he has been heralded as one of the best British actors of his generation, and was particularly praised for his harrowing portrayal of the paralyzed Falklands soldier Robert Lawrence in Tumbledown, it was not until the televised version of Pride and Prejudice that Firth's film career took off.

He lives in London with his wife, Livia Giuggioli, an Italian filmmaker whom he met in 1996 while they were both working on the film Nostromo. They were married in June 1997 and have two sons, Luca and Mateo, aged 8 and 6.

Firth can be serious and intense, but a twinkle is never far from his eye and he has the ability to detect humour in most situations. He has the comedy sequel St. Trinian's 2: The Legend of Fritton's Gold coming out soon and he supplies the voice of Scrooge's (voiced by Jim Carrey) nephew Fred in Disney's A Christmas Carol. But, he concedes, he has yet to be offered the starring role in an epic, big-budget blockbuster.

"They're not bombarding me with offers although the ones that have come along have been too preposterous to contemplate, so it's not as if I spend every day resisting $20 million paycheques," he laughed. "I work with the options I have in front of me and my reasons for choosing a job can vary enormously depending on the circumstances. Sometimes I take a job because it's a group of people I'm dying to work with and sometimes it can be a desire to shake things up a bit and not to take myself too seriously."