`If you love and believe in a film, you'll do anything. I would'

She piled on 40 pounds to play a podgy loser in Muriel's Wedding, and lost 14 to play the glamrock wife in Velvet Goldmine. Acting, not ego, is everything to Toni Collette. No wonder the down-to-earth Australian actress is in big demand

WHILE THERE is undoubtedly more to life than appearances, it has to be said that Toni Collette is looking rather bizarre on the day we meet for our interview. The Australian actress sits in the lobby of a five star hotel wearing a pair of big, beige ug-boots over a pair of stripy tights with a long, patchwork-patterned jacket. Looking like a cross between bohemian luvvie and a dedicated follower of slob-chic, Collette reminds me of no-one so much as our own dear Emma Thompson.

Collette, however, seems completely at ease, both with her self-image and our impending interview. Perhaps this isn't so surprising; at only 25, Collette has already survived five years of media scrutiny following the enormous success of Muriel's Wedding, when she floated euphorically down the aisle as podgy Muriel and into the hearts of Abba fans worldwide. The film quickly pushed the young actress from minor Australian celebrity onto the international film scene with major roles following in Emma opposite Gwyneth Paltrow, The Pallbearer with David Schwimmer and the much-anticipated Velvet Goldmine with Ewan McGregor. Now Collette can be seen playing a sympathetic detective in the just-released British heist comedy The James Gang alongside Scottish actor John Hannah.

Collette's acting choices so far have displayed a marked willingness to work with first-time directors. Just as Muriel's Wedding was the feature- film baptism for its writer/director PJ Hogan, who went on to Hollywood success with My Best Friend's Wedding, The James Gang also uses a first timer, Mike Barker. Although The James Gang is unlikely to set the box office alight given recent reviews, and Collette's role is underdeveloped, Collette defends working with new directors. "They're not set in their ways," she explains. "I find that very exciting and stimulating because, as first-time film-makers, they're prepared to go that little bit further."

The same can be said for Collette. Her enthusiasm in supporting leftfield as well as more mainstream films has kept her credibility intact, despite appearances in Hollywood fluff like Clockwatchers with Lisa Kudrow and the ill-fated The Pallbearer. Last year, for example, she completed the offbeat Australian romantic comedy Diana & Me, about an Australian girl called Diana Spencer who searches out her namesake on a trip to London (unlikely to see the light of day for years, for obvious reasons) as well as the female lead in another Australian film The Boys, an intensely powerful, disturbing portrait of a dysfunctional family in Sydney's violent Western suburbs, from yet another novice director. "There was no f***ing money involved," she says, "We were all there because we wanted to tell the story." Well-received at the Berlin Film Festival, The Boys allowed Collette to show a previously unexplored gritty edge to her talent, a tactic which which didn't go unappreciated by critics.

A "new" Collette will also be on show in Velvet Goldmine, due for release later this year. Having famously piled on 40 pounds for Muriel's Wedding, to the extent that no-one actually recognised the "real" Collette at the film's premiere, Velvet Goldmine required Collette to slim down so she could squeeze into the film's skin-tight Seventies glamrock gear. No ravishing beauty ("Todd Haynes cast me from the inside, which gave me a lot of confidence," she admits, frankly), Collette is nevertheless very appealing and sexy as the hedonistic Mandy in the film, which earned a special jury prize for Artistic Contribution at Cannes this year and which has divided the critics. Love it or hate it, Collette obviously has high hopes of Velvet Goldmine's success, and clearly enjoyed being part of the project. "It was all sex, drugs and rock `n' roll, man!" she explodes enthusiastically. "I loved the dressing up, the make up. Lots of sparkle, lots of shine, y'know? I had 11 different wigs, I had a see-through chainmail dress and a kind of chinois, a tight Asian dress made out of this most amazing gold and leopard skin fabric."

Her most outrageous outfit, however, had nothing to do with clothes at all. "Go the sex scene!" she giggles. It was the first time Collette had appeared naked on screen, and "I was freaking," she says, "but then, when the cameras rolled, Jonathan (Rhys Meyers) and I just relaxed and the crew were like, `OK, cut, cut, cut!' It was great fun! I think that when you're involved in the telling of a story it's amazing what you'll do. If you love the film and believe in it, you'll do anything. I would."

There's something very disarming about Collette when she talks about film. Although she occasionally nudges close to cliche (lots of "falling in love" with projects and cast/crew, who are all "wonderful people") for the most part there's a real sense of her purpose and lack of pretension. Collette herself appears largely unaffected by fame, her "normalness" perhaps the result of growing up in a working class family in Sydney's rough Western Suburbs, where she determinedly left school at 16 to go to drama school in Sydney, before bulldozing her way into theatre (earning a Sydney Critics Circle Award in 1992, aged 19) and picking up her ticket to international fame (and an Australian Academy Award) in Muriel's Wedding.

Collette's Australian roots remain strong, and she still seems as happy to be at home in Australia as anywhere else. Or perhaps "happy" isn't quite the word. Despite the obvious pluses of being a celebrated young actress, Collette at times carries an air of ruefulness behind her big smile. "It's not normal at all," she explains of her lifestyle, "but then, it has to become normal, otherwise how do you survive? I did go through a stage of thinking acting was crap after Muriel. The success of the film was just so extreme that it made me stop and re-evaluate everything - my privacy, my future, what I really wanted.

"There's this tattoo at the top of my bum crack," she continues earnestly. "It's this little Celtic mermaid, and the story behind it is the eternal sea." She looks at me closely, to see if I understand. I nod knowingly. "You know," she continues, "the constant change and waters constantly moving - that's acceptance. That's what I try to do every day. I think it's important. If you're fighting your own f***ing existence, how can you possibly be happy?"

Maybe Collette's move to London will act as the watershed. She has plenty of friends over here, she says, and with the British film industry still buoyant, it makes sense to be based in the UK. On the other hand, she admits, she'll still have her own demons to wrestle with. "I think I have a problem with time," she muses. "I'm very aware of it. When I turned 25 last year, I felt I had to do something to mark the milestone, so I shaved my hair off. Time is a funny thing - we think we've got so much of it, but I think it's dangerous to live in the future and dangerous to live in the past. And yet I find it impossible to live in the moment." She smiles. "I'm working on it, though."