Miss Tyler is Liv-ing it large

There's something slightly shocking about Liv Tyler telling me that her new film is the first she's made 'as a woman', as opposed to a teen ingenue. But a woman she is in One Night At McCool's - with boobs, blazing red hair and balls enough to deal with the dysfunctional queue of men slobbering all over her.

It's an offbeat comedy-thriller that might have been a little-seen independent were it not for the involvement of producer Michael Douglas. Yes, that Michael Douglas. So enamoured of the project was he that he took a role too, which in turn attracted Tyler, Matt Dillon, John Goodman and Paul Reiser, healthy 'names' all. Tyler took the film for entirely self-serving reasons: it was all about her character, Jewel Valentine, and the effect she has on three men one night.

'It's so hard to find parts where you can shine as a woman. I don't mean that in a complaining kind of way, but more than 60 per cent of the scripts I get are about a guy and there's just some woman in there at some point. It's so frustrating.' She knows she had it too good - too young. 'Yeah, I was spoiled. My first film was Heavy [which won her raves] and then I did Stealing Beauty.' Bertolucci's lyrical coming-of-age tale showed that Heavy was no fluke, and the girl who'd hated modelling had a deft talent for doing something rather more animated in front of the camera.

'Even when I made Stealing Beauty, I knew it would never be that good again. But I wanted to find something else that just gave me a feeling.' One Night At McCool's also gave her feelings she wasn't counting on. 'It was a struggle sometimes, just being alone with a bunch of men. Before I had always been a child, in a sense, or a teenager.' The now 23-year-old had certainly relished having a father figure director around to cosset her. She had that with Bernardo Bertolucci and also with Robert Altman, with whom she has made two recent films, Cookie's Fortune and Doctor T. And The Women. 'Bernardo loved me and took care of me. So did Bob. This was my first film out on my own in Hollywood and I felt vulnerable, as if I had to really fight for myself. But I learned a lot about how to handle myself, and how to be strong and confident.'

Tyler does not seem the sort of girl to lack confidence. She insists, though, that while she's no ugly ducking, she was 'not the pretty blonde popular girl' growing up. 'I was loud and chubby and tall. Really tall. All my friends came up to about my armpit. There are pictures of me then that are so bizarre because I had boobs. I was completely developed by the time I was 12. And it's funny, because my sister's 12 now and she has a size nine shoe already [a UK six] and she's very tall.'

Liv is preternaturally young and fresh-faced, her skin white and flawless, her cheeks and lips naturally rosy. And there may be just a hint of a flush. When she entered the room, she was late and full of apologies. She'd run into Geoffrey Rush, who was sitting at a table by himself and invited her to join him. She told him she had an interview to go to, but couldn't resist. 'He's so amazing. I schmoozed with Geoffrey Rush! And it's so funny because when I was making Onegin at Shepperton Studios, he was doing Shakespeare In Love there and I used to see him eating by himself.' She is definitely starstruck and insists she doesn't normally sit down for lunch with idols she doesn't know. 'Only in California, in the fancy garden of the Four Seasons Hotel.'

It's easy to see why Tyler was nervous about playing Jewel, who is clearly not a girl-woman but a vixen unashamed of using her physical potential for sometimes evil ends. More embarrassing, though, is a car-wash scene, filmed in slow-motion and showcasing more flesh than foam. It will undoubtedly become something of a signature Liv Tyler scene. And typically, when Tyler snuck into a showing of Traffic with her dad because the McCool's trailer was playing with it, it was the scene featured heavily. 'I was so embarrassed,' she cringes. 'But I'm embarrassed about a lot of this stuff. You know how hard it is to listen to yourself sometimes? Like when you hear a message you've left on someone's answering machine and you think, "God, do I really sound like that?" Then imagine what it's like to watch yourself in a scene like that.'

Steve Tyler, Liv's rock-singer dad, was either dumbstruck by his daughter's blossoming, or just behaving the way she says he usually does. 'Even when he comes to see my movies, he just sits there totally silently. I have a feeling he's sort of in awe because he doesn't know a lot about what I do and I think he's really fascinated by it.'

Tyler is engaged to another rocker, Royston Langdon - frontman with Leeds outfit Spacehog - but that doesn't mean she doesn't remain an object of adoration for multitudinous boys to men. Can she deal with it? 'Well, I don't see that in my normal life, only from the media side. I may see someone looking at me while I'm walking down the street, but that might be just because they recognise me. I don't sit around thinking, "Well, he noticed me."' What she finds weirder is the constant scrutiny. 'For me, movie-making is mostly about the life experience I have while making the film. Maybe I get that attitude from my father, because I've seen the ups and downs he's been through. But I think that's a healthy way to think, because I can't control what happens when a film comes out or whether it's going to do well. It just seems to me that when you're a kid living at home, the world seems so different and easy. But I can't complain. I'm very happy, and anybody's job is difficult.'

Tyler cannot hide her contentedness, nor the sparkling diamond engagement ring on her finger. In McCool's, her character is obsessed with putting together her dream house. Is Liv the same? 'Totally. I'm looking for a house in New York right now.' She can't wait to start nesting and seems a typical Cancerian homebody. 'I usually work for a year and then take a year off. That's so important to me because I like to be home. I can't stand being away so much, and away from what's important to me. It just makes me feel uprooted.'