For Anne Hathaway, August 3 every year means a private celebration on a special day that has nothing to do with birthdays or anniversaries.

It's the date the film The Princess Diaries was released in the US in 2001 - the date, she says, her life changed.

"That was the day my dream came true. That was the day the fairy tale started," she says with a smile, thinking back over the tumultuous decade in which she became the "It" girl of the moment, with a string of cinema hits to her name. She is, says one Hollywood executive, the only 20-something actress studio bosses entrust to carry a big-budget film.

Hathaway keeps a hectic schedule, and we talk in New York during a whirlwind round of interviews she is doing for One Day, one of the most hyped, if flawed films of the year, while filming the latest Batman instalment The Dark Knight Rises, in which she has achieved a long-held ambition to play Catwoman. At the same time she is supervising renovations on her house in Los Angeles, buying crate-loads of Carrera marble and choosing a colour scheme.

"I love lots of colour and I love mishmashes of things," she says. "My style is very eclectic and a little bohemian." Then she adds, laughing: "I like a little bit of glamour thrown in, too."

The dark-haired, dark-eyed 28-year-old with the wide smile is herself equal parts Hollywood glamour and New York funky, having been born and brought up in Brooklyn, where she has another home and where she spends what little free time she has with her boyfriend of three years and fellow New Yorker, the actor Adam Schulman.

The morning we talk she is wearing a monochromatic orange-blue-and-cream Gucci mini-dress ("I'm being fancy today," she says with another laugh) and Alexander McQueen shoes, although in her private life she forgoes the film star look, adopting a tomboy appearance with jeans and beaten-up boots. She wears a silver ring inscribed with the Sanskrit word for freedom that she bought at her yoga studio as a present for herself.

For someone so instantly recognisable she seems startlingly unpretentious and down to earth, and even now has not totally come to terms with her fame. She seems more like Anne the normal young woman rather than Anne the star, I suggest.

"I forget about that second person you mentioned," she says, "so I'm constantly awkward when people come up and ask for an autograph or a photo because I genuinely forget. I'm always flustered and I'm sure people think I'm very weird."

She tries to not be affected by the attention and luxuries of a film star life that are available when she wants to indulge herself.

"I try not to get used to it," she says. "It's a fleeting thing and I try to keep things very normal. I do my own dishes. Do my own laundry. Change my own sheets. I'm fortunate enough to have been granted access to a world of luxury that I wouldn't have had if my career hadn't gone as well as it has. So I know that it's not inherent to my core values."

She thinks for a moment, and adds: "That being said, it's a beautiful world and it's a world full of intelligent, creative people who love beauty. So I've learned to appreciate it but not rely on it."

Hathaway likes to laugh and joke and appears to be someone who would be good company on a night out. In fact, when she was in London to film One Day, the romantic drama based on David Nicholls's international best-seller, she spent a lot of time before filming began hanging out in pubs and talking to people in order to capture an English accent. Her research paid off, as she certainly sounds authentic, although also as if she talked to customers from different parts of the country; to an English ear, her character seems to vary from Yorkshire to London with a bit of Liverpool and Birmingham thrown in.

In the bittersweet One Day, which shows the ups and downs of a relationship over a long period of time, she plays Emma Morley, a witty, insecure, bookish girl who forms a close and emotional friendship with the privileged and occasionally obnoxious Dexter, played by Jim Sturgess.

Sturgess says of his co-star: "Dexter tells Emma that she's 'the smartest person I know'. Well, there's a lot of Emma in Anne. She has an intellectual wit, and on the set I'd be reading a foolish magazine and Anne would be reading a high-brow novel. She's lovely and we got along straightaway."

Emma's character made a big impression on Hathaway, and she says it has changed her way of thinking to a certain extent.

"It's not that I was hard-hearted or anything like that, but any hardness in my heart really softened and I began to think about things differently," she says. "The movie really made me appreciate the fact that life is right now. Life is this moment; the present is the only thing we can count on. I find myself thinking about that a lot more and trying to stay in the present and making choices in my life that support me doing that.

"It takes some people longer than others to find themselves and blossom and both Emma and I are late bloomers, so I had that in common with her."

"You - a late bloomer?" I ask, having seen her confidently walking red carpets, posing for photographers and giving interviews since she was 18.

"I think when I started I probably projected a confidence that I didn't feel and a sense of self-worth I certainly didn't feel," she says. "Over the past few years I feel a lot more centred and a lot more specifically myself and a lot happier with the choices I make. So when I say I'm a late bloomer I guess I mean feeling happiness and contentment is something that bloomed late for me."

Always honest, she admits to some mistakes in her relationships.

"Sometimes you put your heart out there and guys just do the dumbest things and you weep about it," she says. "And other times it turns out better than you could have ever imagined. So you gotta keep trying."

There's nothing that endears a star to her fans more than love's travails and a bad boyfriend or two, so instead of condemnation she received sympathy and affection when, to her shock, her Italian boyfriend of four years, Raffaello Follieri, was exposed as a fraudster and was jailed for 54 months in 2008.

At the time she pluckily gave interviews in which she talked about her train wreck of a romance and gamely endured the jibes of late-night talk show hosts, although it was a traumatic and unpleasant time for her.

"I got through my pain the way I always deal with unpleasant things," she says, "and that's to make a joke of it."

With that all behind her she is in love again, happy and content in her relationship with Schulman. After she finished filming One Day and before she started work on The Dark Knight Rises, they snatched time to go on a romantic holiday to Italy's Amalfi coast.

"I'm enjoying myself very, very much," she says. "Happiness is a nice feeling."

The daughter of a lawyer father and an actress mother, Hathaway started her performing career as a soprano, singing at New York's Carnegie Hall when she was 14. At 17, she appeared as one of the leads in the short-lived television drama Get Real.

After leaving university she became an overnight sensation in the family fable The Princess Diaries as an innocent teenager who discovers she is a princess. She landed the role after she charmed the director Garry Marshall by accidentally falling off her chair at her audition. The film was a huge success and Hathaway found herself a reluctant role model to teenage girls everywhere.

It was an image she found difficult to get away from, but she succeeded by taking daring roles that included racy scenes in Havoc; a supporting role in Brokeback Mountain; the aspiring journalist with the boss from hell in The Devil Wears Prada; as Agent 99 in the comedy Get Smart; and as Maggie, a free-spirited artist suffering from Parkinson's disease in Love and Other Drugs.

"It's not the case of 'Once a princess, always a princess', and I'm not 'the girl who was in The Princess Diaries' any more," she says. "But I'm proud to have been a part of something that is becoming a classic film for children."

She will soon get to display her singing talents on screen when she portrays Judy Garland in a project that is in the works, although, she says: "I don't feel that I'm a strong enough musician yet to release an album or to try to have a career as a singer. I think I'm a strong amateur."

But first she has to finish work on The Dark Knight Rises, which the director Christopher Nolan is filming until November.

"It's the biggest movie I've ever worked on," she says, "but because Chris is so specific and nuanced with all the scenes and characters, it feels like a little independent movie. Because of The Princess Diaries people ask me if I'd always dreamed of being a princess. Nobody believed me when I said no, but I wish I'd told them the whole truth which was 'No, I dreamed about being Catwoman.'

"Catwoman is the coolest. She is fierce and mysterious and complicated and I was more attracted to her than I was to any princess or Cinderella. So when I put the cat suit on it was a dream come true. I just felt fierce, too, and I felt fun and I felt really, really lucky."

Life is a joyous adventure for Hathaway, who tries to make the most of it.

"I try to do the things I love in a more consistent way," she says. "I'm pushing myself to do things like yoga a lot more. I have a pretty busy life and I'm all over the map so sometimes it's easy just to say: 'Oh I'm tired. I'd love to just lie on the couch and watch a movie.' But I push myself to get out there and do something. I'm happier doing things than not."

And for Anne Hathaway there is always plenty to do.

One Day opens in UAE cinemas on Thursday.

The Hathaway File

BORN November 12, 1982, Brooklyn, New York

EDUCATION Milburn High School (Milburn, New Jersey), Vassar College, New York University

FAMILY Father Gerald, a lawyer; mother Kate McCauley, an actress; two brothers, Michael and Thomas

FIRST JOB Appearing in the television drama Get Real at the age of 17.

READING Midnight's Children by Salman Rushdie

LISTENING TO Adele, T-Bone Burnett, Eddie Vedder

FAVOURITE DESIGNER James Banks

FAVOURITE CLOTHING ITEM Rick Owens leather jacket

HOBBIES Yoga, bicycle riding

FAVOURITE DESTINATION Positano, Italy

BIGGEST FEAR Isolation and loneliness

Casting against type

Anne Hathaway has starred mostly in family films or rom-coms, but has also accepted roles in some edgier films. Among them:

HAVOC (2005) Hathaway plays a spoiled socialite in this Barbara Kopple drama and appears nude in some scenes. She rebuffed film critics who said that her taking the role was a bid to be seen as a more mature actress. The film went straight to video in the US.

BROKEBACK MOUNTAIN (2005) Nailing her role as a spoiled rich Texas girl, Hathaway is part of a strong cast behind Heath Ledger and Jake Gyllenhaal. She plays Lureen Newsome, the wife of the Jack Twist character portrayed by Gyllenhaal, in this much-honoured Ang Lee film.

PASSENGERS (2008) Hathaway plays a psychotherapist who treats five survivors of a plane crash in this convoluted psychological thriller that was savaged by critics and rejected by film-goers. It cost US$25 million (Dh92m) to make but earned less than $5 million at the box office.

RACHEL GETTING MARRIED (2008) Critics raved about Hathaway's "raw, spiky" performance in this Jonathan Demme drama as a young woman who's released from drug rehab to attend her sister's wedding. The actress was nominated for an Oscar but lost to Kate Winslet in The Reader.

ALICE IN WONDERLAND (2010) Hathaway's White Queen is one of few characters that did not require digital manipulation in this Tim Burton computer-animated/live-action fantasy adventure film. Hathaway described her interpretation of the role as "a punk-rock vegan pacifist".