In a candid moment, actress Sarah Polley, last year's It Girl at the Sundance Film Festival, admits to being what she calls an inverted snob. By this she means that she thinks acting is a useless profession and actors take themselves way too seriously. But then there's a point at which she realizes that she's taking too seriously the whole issue of actors taking the business too seriously.

"Why is what you do any more important than someone driving a bus?" she says earnestly. "I tend to think of this as so shallow and stupid. Then I go the other way. You can choose to make it the most shallow thing in the world, but it doesn't have to be."

Polley is really hung up about Hollywood and the star system. Much against her will, she appeared on the cover of Vanity Fair's annual April issue of hot young actors, which she earned with her breakthrough role as a paraplegic in "The Sweet Hereafter," her sullen checkout clerk in "Go" and her Pygmalion in "Guinevere," which is opening this fall. Her ambivalent attitude toward this success made her an almost irresistible target for her colleagues. After all, most actresses would love to have her problems.

"She's got a really interesting existential dilemma," says "Go" director Doug Liman. "She's basically becoming the person she hates. During the shooting of 'Go,' I would always joke with her, just to get her angry, about the fact that I was sure that in the next year I would be picking up a Vanity Fair and she'd be on the cover. Thinking that would be a movie down the road, not knowing that it was going to be our movie. It also put me in the uncomfortable position of Columbia publicity asking me to convince her to do Vanity Fair. I was like, 'Oh, my God, that's the exact magazine that I would chide her about and say that there can be no bigger. . . .' "

Sellout? Polley's attitude might seem precious, especially given the business she's in, but she does have an acute understanding of what's really going on.

"I don't mind if someone wants to photograph me because they've written a piece, but ultimately no one wants to photograph me," the 20-year-old says. "They want to photograph something they helped to create, so they have to manufacture some kind of image for you, and you either consent or you don't. There are clothes to be sold, and you're there to be sold, and there's a movie to be sold, and you end up being part of an advertising machine. I'd like to think that whatever I do with my life is really important, whether it's acting or something political."