Jessica Alba: 'I don't look as I feel'. Photograph by Colin Bell

The Oscar-winning director of Titanic has chosen the 18-year-old as his star for a new television series, Dark Angel, an expensive project he is writing and directing, with the aim of securing it the kind of global following enjoyed by The X Files. But Alba, who will play a genetically enhanced, part-feline, part-human character, in a story set in San Francisco in 2030, has already shown her claws.

With intense physical training for Dark Angel already in full swing - filming is due to start in August - she has taken the lead role in a small-budget movie for Sky Pictures, called Paranoia, which has been shooting on the Isle of Man. It's written and directed by the Australian John Duigan - who cast Kidman in his 1980s TV series Vietnam, then in the 1989 film Flirting, and went on to make Sirens and Lawn Dogs. In an unusual sequence of events, Alba dispatched a video of her work from Los Angeles to London, spoke to an impressed Duigan by telephone two days later, was hired two days after that and within another two days was arriving at the island's small airport near the capital, Douglas, to start work the next day.

Cameron, known for being demanding with actors, was left to seethe quietly in Hollywood as he worked on plots for the new series. "He has not spoken to me, but I know he is not pleased she is here," reports Duigan. Considering the Titanic star Kate Winslet famously recalled that Cameron "has a temper like you wouldn't believe", Alba remains remarkably calm.

"Jim is an amazing writer and director who will appreciate that working over here will only help me as an actress," she says. "And John Duigan had written such a brilliant script for Paranoia, it was impossible to resist. It is a thriller that twists and turns and keeps everyone guessing until the very end. I am also learning a lot from a really strong cast." Alba is obviously a fast learner; she already knows what to say to keep sharp egos at bay.

But casting is certainly impressive on Paranoia, with Jeanne Tripplehorn, who can count star turns in Basic Instinct, The Firm, Waterworld and Sliding Doors among her successes, as the second female lead; Iain Glen, fresh from his triumphant two-hander stage play, The Blue Room, with Nicole Kidman, in London and New York, is the male lead. There are also key roles for Ewen Bremner - he played Spud in Trainspotting - and Kevin Whately, who has punched his weight on television with the likes of Inspector Morse and Peak Practice.

It makes the fact that two experienced directors such as Cameron and Duigan are slugging it out over the services of one teenager all the more intriguing. "I had been searching high and low for someone to play this principal role," says Duigan, who has cast Alba as a rising young fashion model called Chloe. "Everything and everyone else was in place. Then we found Jessica, who has exceptional maturity, poise and style." He also observes, pragmatically: "It's a good job we've got her now, because she will soon be outside our price range."

Cameron prefers, for the moment, not to make any public comment, since he wants Dark Angel, with the first of its 13 episodes due to be screened on America's Fox television in January 2000, to remain something of a grand TV event on release. Instead, he simply dispatched two Hollywood trainers to the Isle of Man to continue Alba's daily workouts. Their superfit figures, barking out instructions, make an incongruous sight amid the splendid countryside and old-fashioned charm of an island that still has horse-driven trams and steam trains as public transport.

"I do running, strength training and gymnastics," says Alba. "My character is the dark angel, called Max - a bike messenger during the day and cat burglar at night. Her home is on the street, she sleeps catlike in places like the Golden Gate Bridge, and she can see, hear and move much better and faster than humans. She does not have a family or social security number, and the government would have her killed if she was ever found. They want her, plus other genetically enhanced people, to stay a secret."

For the 44-year-old Cameron, the whole dotty-sounding project, for which he has signed Alba to a minimum five-year contract if the first series is a success, is part of the deal he made with Twentieth Century Fox three years ago. The studio was pouring money into Titanic, which seemed to be floundering amid mounting costs and problems, and Cameron pledged himself to a television project in return. The fact that the film went on to gross £1.8 billion at the box office, making him rich beyond every expectation, does not apparently change either his commitment or enthusiasm for Dark Angel.

"He is so excited, anyone would think he is directing for the first time," says Alba. "I met and read with others from his company before seeing him, and did what amounted to a workshop with him for one hour. I thought: if I don't get chosen, what have I lost? I was happy just to work with him and learn. It was like something you would pay for."

Such an attitude, coupled with what was obviously an impressive performance, was duly rewarded with a contract. It is the sheer driven enthusiasm of Alba - who was born in California, started taking acting lessons at 12 and lists her background as part Mexican, Italian, English and Danish - that has clearly made such an impact on Hollywood. She is also blessed with an elegant, 5ft 7in figure, brown eyes, brown hair and looks that can appear both sultry and sexually charged. "I don't look as I feel," she says. "But that's why I love to play characters like kick-ass girls who are messed up."

After television appearances in series such as Chicago Hope and single dramas - in one, she played a pregnant girl who has to give up her baby - she will be seen on the big screen in Britain for the first time in August, in Never Been Kissed. It's a charming romantic comedy starring Drew Barrymore as a Chicago reporter who enrols as a high-school student to investigate new attitudes on sex, drugs, music and teen relationships.

The film, for which she was hired directly by Barrymore in her capacity as executive producer, has already grossed more than $50m since its release 10 weeks ago in America. "I play one of those girls I used to hate but would loved to have traded shoes with: quite bitchy, the coolest clothes, liked by boys. My outfits became smaller with every scene, with the tiniest tops and a skirt which hardly covered my bum. I just went for it."

Another movie she has completed, Idle Hands, is yet to be released. "I play a cool girl called Molly who rides a motorcycle, plays bass guitar and writes her own music," she says. "She makes friends with a crazy, messed-up guy whom she can control. She's a wild, saucy girl who pushes him to see how far she can go. When I like a guy, I do not know how to act and I seem distant, because I don't know what I am doing and feel like a dork. Molly would just take him up to her bedroom."

She holds up Barrymore as being a perfect example of how far, and how quickly, she can go. "I admire how Drew has beaten her earlier problems [drugs and alcohol]. She is only a few years older than me but has control over her career, while remaining a real sweetie. She has her own company, is able to suggest film ideas and get them made by working very hard, with great determination."

Alba has worked hard, too: she moved to Australia, aged 14, with her mother, Cathy, as chaperone, to appear in 44 episodes of Flipper. At 16, during school holidays, she spent six weeks on an intensive acting course at the playwright David Mamet's Theatre Company in Vermont, being taught by Mamet and Fargo's award-winning actor, William H Macy. "I was the youngest, and some of the older students were really patronising towards me," she says. "But it was funny to see how they behaved. Many in their early twenties just wanted to be kids again, thought they knew everything and were full of political correctness about gay rights, women's lib and religion. I was there just trying to become good at what I do."

She is now proving just how good while working on Paranoia. "I think," says Duigan, "that with Jessica Alba we are seeing the start of a brilliant career."
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