Get ready for real Diesel power

Vin Diesel has presence, a calm rangy presence that fills his suite in London's Dorchester Hotel.

Imposing but genial, the 6ft 4in New Yorker lounges on a settee barely able to accommodate his muscular frame and speaks in a long, slow, deep rasp. The voice exudes a laidback confidence which is hardly surprising. At 33, Diesel may not be the youngest star in the Hollywood firmament, but he has made his years spent in obscurity work in his favour. Back in February, when his first two major on-screen roles, in the indie drama Boiler Room and the sci-fi thriller Pitch Black, hit US cinemas on the same weekend, American critics hailed him as the first major star of the new millennium.

The roles provide a sharp contrast. In Boiler Room he's a besuited telemarketer, a shopfloor dynamo in illegal stock trading who reveals a surprisingly tender side. But it is as Riddick, the sinister blood-sucking multi-murderer who oozes a sexual menace and malicious intent, yet emerges as a possible saviour for the cast of Pitch Black marooned on a distant planet, that Diesel really makes his mark. Stealing a march on the summer blockbusters, the relatively low-budget film was an unexpected box-office smash. A sequel with four times the budget is planned and one of several Diesel-dedicated websites features him in a Riddick cartoon strip, while another invites readers to submit future Riddick storylines, which they have done - in their hundreds.

'It's bizarre, definitely bizarre. If you'd asked me as a kid what I wanted to be, I'd have said an actor,' he grins. 'And when everybody had stopped laughing, I'd have said, "And a superhero." Well that's exactly what's happened.'

But, as befits a guy who spent almost a decade working as a bouncer in the nightclubs of New York and Los Angeles, Diesel has all the angles covered. He has already written, directed and starred in two of his own films. Made on a shoestring budget, the full-length Strays (financed by a stint spent telemarketing, an invaluable aid to his future role in Boiler Room) and the short Multi-Facial may have only been seen on the festival circuit, but the latter was enough to convince Steven Spielberg to write a part for him in Saving Private Ryan, and for director Brad Bird to hire him to voice the lead role in the animated adaptation of the Ted Hughes poem The Iron Giant. Making the films has also given Diesel a keen perspective on his own career. Wary of being typecast by his physique, he chose to do Boiler Room 'because you get to see me in a suit. Seriously, it's actors insurance - films like that keep your credibility alive for people who aren't smart enough to look deep enough into sci-fi films.'

As an oversized, musclebound teenager with his sights set on the big screen, Diesel says that seeing Arnold Schwarzenegger in Terminator and Mel Gibson in Mad Max were empowering experiences. Gibson remains a touchstone. 'I'd like to see myself like him - in a position where I can make any film I want to make.'

Born and raised in New York's Greenwich Village, he was the son of a theatre manager/drama teacher father and a mother who combined astrology and psychology. The family - he has two sisters and a twin brother - lived in heavily subsidised apartments for non-profit-making artists. 'You had a wonderful community of jazz musicians, sculptors, painters, dancers - everyone was creating, being their artistic selves. It meant working for art rather than being governed by money, which is probably why I've never made any during much of my life.'

He discovered acting for himself - at the tender age of seven he had his first paying role in a local experimental theatre. 'I became ambitious very early. I was an extrovert of the highest calibre,' he recalls. 'My little sister is 27, and people ask her what's it like now that big brother is a star. She says it doesn't feel new - "When he was running around the neighbourhood and when he was a bouncer everyone knew me as Vin's little sister." I was the kid everyone knew, the one in the family who was always pushing.'

Vincent is the family surname - as a young actor he adopted his stage moniker and prefers to keep his real Christian name and 'complicated' ethnic make-up a mystery. Was there much competition between him and his non-identical twin Paul, now a film editor? 'I imagine early on there was, but not now he's so far ahead of me - he has a family and two beautiful kids - that anything I do pales in comparison. For me, having a family is the ultimate dream, but it's nowhere on the horizon. It's why I did The Iron Giant - I wanted a five or six-year-old kid to go to school and be able to tell their friends my dad is the Iron Giant.'

Preparing for the sleek, panther-like Riddick in Pitch Black he changed his physique by taking up yoga and pilates - the compulsive weight training that began at 15 and became a virtual addiction when he reached his twenties has slackened considerably and changes depending on what is required for his next role. But the weight training was essential for the periods he spent employed as a bouncer, a job which he insists taught him a lot. 'You have to execute diplomacy and read people in ways that are imperative to your existence. You're not a cop, you don't have a gun or a bulletproof vest. You have to decide when to be physical and when to be diplomatic. The novelty wore off after a couple of years - it was too dangerous a lifestyle for me to be involved in. There was a lot of degenerates, you get that in any community, the scumbags who wanted to ruin everyone else's party. That's who we went after, like if a guy squeezed a girl's ass it was a problem that could be rectified in many ways. I viewed it in a heroic fashion - when you come to this club you're going to have fun, you don't have to worry about anything - you got me to look after you.'

Diesel had abandoned Multi-Facial - 'kind of about race and identity, hard to explain, you have to see it' - when his father persuaded him to finish it. Someone sent a tape to Spielberg who invited him to meet him on the set of Amistad. 'He said it touched him - he was very generous. That was a special day. We talked only for 25 minutes but it was very deep. We immediately connected. The next thing I knew I was on a plane to London to shoot Saving Private Ryan. Surreal.'

And yet he seems remarkably unfazed by developments since Spielberg conferred his Midas touch - 'that's because I'm not 16'. Next up he stars alongside John Malkovich and Dennis Hopper in Knockaround Guys. He calls his own production company One Race because 'in the earlier part of my career nobody knew what to do with me but now I find I can do so many things because I come from origins that are a little ambiguous. I think I represent a certain future.' Currently he's developing Doorman, the script based on his time as a bouncer, and a romance centring on a group of Navy SEALS who return from black ops. Meantime he's heavily involved in discussions about how Riddick's character will develop in the Pitch Black sequel.