There’s a vacancy right now for America’s sweetheart. Julia Roberts, Renée Zellweger and Reese Witherspoon have graduated to dowager roles. Hollywood’s most famous twentysomething, Lindsay Lohan, has just checked into rehab. No wonder, then, that the studios are going crazy for Anne Hathaway. Her Bambi eyes and Snow White colouring combine to give her an air so wholesome, I’m tempted to ask if she’s free to baby-sit tonight.

Best known to the over-21s for playing Andy Sachs, the nice girl who nearly sells her soul for a Chanel discount card in The Devil Wears Prada, Hathaway has long been an icon of the Bratz brigade, thanks to the phenomenal success of her early films, The Princess Diaries 1 and 2 and Ella Enchanted. But, at 24, she is determined to break free of what she refers to with grimaces and eye-rolling as her “tiara flicks”. She started by whipping her top off in Brokeback Mountain, and now she’s taking the obligatory step of proving she can “do” English by playing Jane Austen in Becoming Jane, a fictionalised account of the author’s early life.

“I rode the one-trick pony for a while, then I figured maybe it was time to come out of hibernation,” she says, curled up on a huge sofa in her suite at the Dorchester, dressed in skinny jeans, a baggy, long-sleeved red T-shirt and giant heels. “First, I had to work through some shit in my personal life. I wasn’t ready to be a serious actress, with all that that entails, because I still had a lot of questions about myself as a human being. But now I’m totally there, and more comfortable than ever just going about and showing what I can do.”

It doesn’t hurt, of course, to have been given a face beautiful enough to launch a thousand male fantasies. Hathaway’s prettiness is the dark and sultry kind that will settle into itself nicely as her twenties progress. Her provocative, Julia Roberts-sized mouth requires no make-up conjuring tricks. As she slowly sheds the slightly prim image, it isn’t hard to imagine her features developing into those of a louche starlet of the first order.

Or maybe they already have, and we just haven’t noticed. For all her perky demeanour, she is at pains to stress that the real Hathaway is far removed from the cheerleader image. “People say I appear controlled, and I can be, but in real life, I’m all over the place emotionally. I cry terribly easily. Just a minute ago, I was reading an article about Kate Winslet in Vogue, and I love her so much, I started crying, realising how great she is and how far I have to go.”

Goodness. Then again, Hathaway is a classic type-A personality, and tormented by self-doubt. She began acting professionally at 16, but has managed to fit in an English degree that she is now finishing, in between films, at New York University. Everything about her breathes focus, and it’s hard not to compare her to the less clear-headed Lohan and her posse. Not for Hathaway night after night falling over in nightclubs, surely?

“You know, Lindsay and I have a lot more in common than people think,” she says. “We’ve all done things we shouldn’t, it’s just I did stuff at college, when nobody knew about it, so I’m not a saint. There’s no moral superiority there. Lindsay’s a nice girl, I like her a lot, and she’s a great actor, but there’s a fascination about her lifestyle that distracts from her talents. I just hope she finds some comfort in the way she chooses to live. I wasted time doing self-destructive things, but it didn’t work. I found you can only dance on so many table tops. I got all that out of my system, and now I’m healthy and I’m grounded.”

She refers again and again to dark times, anxiety attacks and bad relationships, but declines to give details. She was raised in New Jersey — and, yes, she was named in homage to Shakespeare’s wife. Her father is a lawyer, her mother a stage actress “who never got a break”. Does she resent her daughter’s fame? “You’d have to ask her that,” Hathaway says firmly. “She seems completely proud. She’s not frustrated by my success, she’s frustrated by her lack of success. It doesn’t work out for everyone.”

She dates the time of her turnaround from navel-gazer to Pollyanna to three years ago, when she met her boyfriend, the Italian property developer Raffaello Follieri. “He’s brought out so many positive attributes I never had before,” she gushes. “Before I met him, I wasted so much time. I was just annoying and narcissistic, and smelt bad. He’s protective without being possessive, passionate without needing to show his temper. I’m sorry, I know I sound insipid.”

She does, but the way she’s blushing is incredibly sweet. The other influence in her transformation is — surprisingly — Hollywood’s baddest good girl, Angelina Jolie, who inspired her to jump aboard the celebrity charity train and become involved in work in Cambodia and Nicaragua. “I just love Angie’s fearlessness, her provocativeness. Before I met her, I was in this mindset where everybody hated me, and I hated me, and everything was too much. She made me see how silly I was, how I couldn’t just sit on my ass.”

The ass-sitting days have well and truly gone, and 2007 will be a packed year. She’s currently filming a psychological thriller, next up is a film version of a hit American television series, and there are other projects brewing. “Then I’ll be sick of myself and do theatre instead. But it’s so nice not to have that nagging ‘I’ll never work again’ feeling. Smug and employed, that’s how I like it.”

With that, she hurries off to the next room, where her handsome prince Raffaello is waiting, like a former Sleeping Beauty now fully awakened, the tiaras binned.

Becoming Jane is released on March 9

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