Heather Graham is not stupid. This is worth mentioning merely because of a general presumption to the contrary. Maybe it's the bee-stung lips and tousled blonde locks, possibly it's the body with curves straight from an animator's pen. There's every chance it's, like, the Valley-girl accent punctuated with a girlish giggle, you know?

Even more likely is Heather's own assertion that we don't want people to have both beauty and brains because "it's just plain annoying".

Whatever particular combo of attributes leads the casual observer to draw such conclusions, it's not one that 33-year-old Graham herself is unaware of. In a karmic twist, however, it is one she's been able to use to her full advantage.

"For the last year and a half I've been developing material and optioning scripts," she says. "I met with these producers and they were really condescending and I ended up getting the rights away from them because of it."

This lethal beauty/brains fusion hasn't always been Heather's to enjoy: previously it was just the brains. No prom queen, no cheerleader, just a Dostoevsky-loving straight-A student; the classic class nerd herded into specialist classes for those nurturing a high IQ.

She tried to be 'with it'; of course, but her Breakfast Club/Pretty in Pink-inspired sartorial leanings; red summery dresses with white polka dots and black tights weren't fooling anyone. "I just loved shoulder pads," she remembers, "but I got it all wrong and I had the worst style. Everything was all wrinkly".

Things were to get a little more ironed out when she turned 18. Always a keen participant in the school play, she'd set her sights on an acting career and was cast in teen movie Licence To Drive. A year later director Gus Van Zant picked her to play the drug-addicted teen Nadine in Drugstore Cowboy, and a career was starting to take shape.

Forty-odd films later she's run the gamut of roles, from the inevitable sex-kitten (Austin Powers) and hooker (From Hell), through nun (Twin Peaks), sweet girlfriend (Swingers) and space traveller (Lost In Space) to porn star. Er... twice. Most recently in The Guru, and in her breakthrough performance as Rollergirl in 1997's Boogie Nights.

"Hmm, perhaps I should go for the third," she laughs. "The first was just like, well why not, and the second was like; it was just a good script. It's hard to find scripts that make you laugh."

The first also found Heather in a series of compromising positions and very little clothing. Ask if she's comfortable with flesh-bearing roles and it's clear that despite her picture-perfect form she'd rather keep it under wraps.

"To be honest I'd rather never do it because it feels scary," she admits. "Unless you're extremely confident about your physical appearance you're very nervous."

Though physical confidence isn't something one would imagine Heather Graham lacking.

"I think I'm pretty good, but to be naked you feel every wart you have is showing. I'm really working on my confidence but I'm not a hundred percent. Plus the culture is a really sexist one - it's really geared that women have to be perfect physically but men can be whatever. But I think if you can see through that you can say it's just stupid. How can you have a really great connection with another person if you really believe all these things that society tells you?"

You don't think the pressure is on for men now too?

"Maybe. Sadistically I hope it is: fuck it, let them suffer too."

Talk inevitably moves on to the men in her life; Heather's had her fair share of co-stars and fellow thesps to share the limelight with, Heath Ledger, Edward Burns, James Woods and Kyle MacLachlan among them. Currently, however, she's trying to break the habit.

"I haven't gone out with a co-star for a while, which is good - I think it's distracting. When you go out with people you're working with you get confused because you're pretending you're into them, like if you're doing love scenes. You should wait and see if you really are."

Current beau is screenwriter/director and Cambridge grad Chris Weitz (About A Boy, American Pie), who she met on a blind date.

"I went through this period of asking friends of mine to set me up. It kind of didn't work out at first, then it sort of did a few months later. It's fun because there's no aspect of being in the same field and competing. It's so different that it's more interesting. Like 'wow, he writes! That's so cool. Plus he's a really nice person."

Nice as he is, though, co-habiting is on hold for the time being.

"I had two different boyfriends I lived with and I guess at the time it seemed easy, but as you get older you realise more about your own personality. I really like to make other people feel comfortable and sometimes I try too hard. So now I realise that I really like being alone because I'm not at all thinking about anyone else."

Thanks to the recent purchase of a second home - a loft in New York - in addition to her Spanish-style place in the Hollywood Hills, Heather can now be alone in two States, and is loving bi-coastal living. On looking for a place to live, she says she's flexible as long as "I won't want to slit my throat in the morning when I wake up" and seems genuinely surprised at her own material achievements, admitting she feels "like a kid that owns property".

Plus she seems particularly chuffed with the purchase of a sofa that allows her to spill tomato sauce on it without leaving a stain. "It's not something you'd want to be worried about, is it?" she asks.

Along with getting the first films made through her newly formed production company Beach Tree ("the name's got personal significance but I feel kind of gay saying it"), she's next to appear in Hope Springs with Colin Firth, a romantic comedy tagged as "about finding happiness when you least expect it". Is that how it goes?

"Oh, I've no idea. If I had it figured out though I'd be really jazzed."