David's Evolution into comedy

The first thing you notice about David Duchovny is his perfect skin.

It shimmers and it's just soft enough. It has a luminous quality, which must be very luminous indeed, as he's just got off a flight from Australia, which normally makes people look very grey and spent. I once bought a pot of golden moisturiser called Celebrity Skin; now I know it was David who inspired it. He's languid and he's droll; more than anything he's comfortable in his own superskin.

"I never used to be comfortable in my own skin," he says. "I was ashamed of everything. Of being a failure, sex, money, knowing my feelings. I was just very afraid to have everyone know what I really wanted or who I really was."

For the past six years he has been the deadpan, detached Mulder from The X-Files, someone who feels much and expresses little. But that's not really Duchovny at all. He will give you a sound bite that's a seven-course meal, and he knows this is an important departure for him.

He is in London to promote Evolution, a big-budget comedy directed by Ivan Reitman, producer of Ghostbusters and Animal House. It's surprisingly well put-together and I think Duchovny cuts it as a comedic hero of the big screen.

He's exited the comfort zone of the successful TV series - the money, security, the instant identification with the one character. At 40, it's something of a risk. But he says: "At some point, and I may have even passed it, your creative soul begins to wither away a bit. To be perfectly honest, I just passed the point where I felt I was productive. You don't get a lot of sympathy from people, especially from people who liked the show and wanted it to continue."

So was there a defining moment when he'd had enough of X-Files? "No, because that would be like saying it was a chapter heading in a biography of my life. It was more like, 'I'll do this movie, I want to do a comedy.' I also want to write more, direct. I want to do my own stuff; you can't be doing other people's work forever."

While The X-Files still rated top of the box office, the relationship between Mulder and Scully seemed to run out of steam. Duchovny says candidly that his relationship with co-star Gillian Anderson had been reduced to: "I trust her to show up and not waste my time. She does the same. We don't socialise." He also says: "I really don't have that much interest in aliens."

Duchovny's always been hard on himself. An alpha male needing those straight As. "The irony of playing a hero, that's not lost on me because I think that's something a man learns he needs to do at a young age, at least to try to be heroic." He's one of those men who is more in tune with women. When I last interviewed him, he told me: "My best friends were always girls and the people at my school brought my mother in and said: 'We are a little concerned he's gay.' And my mother said: 'No, he's just very sensitive and mature.' She always defended me - which is a great trait in a parent and dogowner."

He has a huge work ethic, instilled in him by his Scottish mother, Meg, who split from his American father Amram when Duchovny was 11. She made all the decisions about money and education, and encouraged him to get his scholarship for Princeton, then later Yale. It was at Yale - Duchovny was researching a PhD thesis on magic and technology in contemporary poetry - that he came across the chance to earn a little extra cash in a lowbrow advertisement. The rest you know. He became one of our most intellectual sex symbols.

No one ever thought his marriage - to actress Téa Leoni - would work or that fatherhood would suit him so well. He said that when he met his wife, "I was at a turning point in my life. A conjunction of timing, maturity, and luck and attraction. It was as if all the pieces fell into place at once. Of course, I thought she was totally sexy, and in a way not like anybody else. In America they think you're sexy if you look good. People think Tom Cruise is sexy. I can't think of anything less."

Duchovny and Leoni first met when they were competing for the same slot on a Letterman show. It was a few years later before they realised they liked each other. They are not an obvious team. She is much more outgoing and energetic. He has more of a potential for self-torture and writing poetry.