Kirsten grows up

Kirsten Dunst is celebrating being part of what could be the biggest box-office hit of all time. Opening figures in America for

Once more Dunst plays the trusting Mary Jane Watson to Tobey Maguire's bumbling Peter Parker. While he secretly becomes the spidery champion of good over evil, she is considering marriage to someone else. But when he saves her from the villainous Doc Ock (Alfred Molina), she is caught in a dilemma. Does she follow her head or her heart? While her heroine in Spider-Man 2 can't quite make up her mind about whether Maguire's Parker can change her life, off screen Dunst is convinced she's found her own real-life hero in her actor boyfriend Jake Gyllenhaal, the 23-year-old star of The Day After Tomorrow. 'It is an amazing time for me,' she says, clearly elated at the way things have gone for her, both personally and professionally. 'I have had a lot of doubts about where I am going and what I am doing.

I feel young. I look young. But now I think something has happened to me which means I no longer have to look back.'

Gyllenhaal, she says, has transformed her from an uncertain and insecure girl alone into a young woman with confidence. 'I have gone from someone who was never too sure of herself to someone who is enjoying life and work as never before,' she says. 'Jake represents a turning point for me - a time of greater awareness and happiness. I realise that I have been waiting for this moment for a long time.'

Bizarrely, Dunst enjoyed a brief dalliance with Maguire on the first Spider-Man film, two years ago. When Maguire injured his back, there was talk of lookalike Gyllenhaal stepping into the role for the sequel. It seemed to work wonders for Maguire's recovery, although Dunst is swift to insist that, 'Tobey is a fantastic actor and makes a great Spider-Man, so everyone wanted him to take the part again. Our friendship had nothing to do with love, though. I've not been in love before now. I'm the pickiest girl on the planet. I've learned that it is rare to find a sexual connection with someone. I was quite happy to wait. When I fell in love with Jake, it felt right.'

Dunst has the kind of looks that are standard issue around Beverly Hills - blonde hair, blue eyes, pencil-slim figure in designer dress. But behind the shrill voice and the girlish talk of love, she is a veteran of 43 movies as child actress, teen star and twentysomething. It is the sort of treadmill that would grind down the most upbeat and secure of actresses. Dunst recalls that while she was playing grown-up roles - such as the pageant beauty in Drop Dead Gorgeous (1999), a manipulator in The Virgin Suicides (1999) and the mixed-up kid in Crazy/Beautiful (2001) --she was full of self-doubt. 'I didn't know much about life or much about sex,' she says. 'A good part of me still felt like the little girl whom I had not left behind. I was beginning to think that things may never change for me. I had all the insecurities of anyone my age.'

It was Gyllenhaal, who last year delivered one of London's most memorable stage performances in This Is Our Youth, who changed all that. They met through his sister, Maggie, 26, who enjoyed her own moment of fame early last year with a notable

performance in Secretary as an employee who enjoyed S&M. 'It was love at first sight,' says Dunst, without a trace of awkwardness. 'We knew we wanted to be together and this relationship has definitely shaped my life. I feel more confident as a person and more inclined to speak my mind.'

Her non-stop acting marathon, which started, aged seven, in the 1989 Woody Allen film, New York Stories, has not run as smoothly as it seems. Her Swedish mother, Inez, overruled the objections of her German father, Klaus, and took her from their home in New Jersey to Los Angeles to jump-start the career she's now enjoying. But there has been a price to pay. The marriage collapsed in the wake of long separations, plus journeys from one side of the country to another. Dunst also has her reservations about having had too much, too soon through her successes such as Little Women (1994), Jumanji (1995) and Wag The Dog (1997). 'I tried to stay humble in school,' she says. 'I put my head down so as not to be noticed. It was scary for me to grow up onscreen. I can't go back and look at those films now. It's like your past being documented for someone else to see.'

Now Dunst appears to be on something of a roll. This year alone she's played a superbitch opposite Julia Roberts in Mona Lisa Smile. Then came Eternal Sunshine Of The Spotless Mind, with Kate Winslet. Her star turn as Twenties pin-up Marion Davies, lusted after by Charlie Chaplin in The Cat's Meow, won her some career-best reviews. After Spider-Man 2, her next role is as an American tennis star who inspires a failed Brit (Paul Bettany) to win the Championships at Wimbledon. 'Why they chose me, I have no idea,' she smiles. 'I couldn't even hit a tennis ball in a straight line. But by the time we had gone through training and tuition on how to move, I was improving by the day. The trainer kept on saying, "Move like a panther, move like a panther." So, in the end, I was prowling around the court and smashing the ball left, right and centre. But, remember when you see it - it is only acting. Don't expect me to win in a real game.'

Spider-Man 2 opens Thur 15 Jul. Wimbledon opens on Fri 24 Sep.