Any actress who has grown up sexy and beautiful, in life or on the big screen screen, will tell you they want to be taken seriously. Charlize Theron, the leggy beauty from South Africa who discarded a modeling career to make a major impact in Hollywood discards her sexy image with a remarkable, unrecognizable turn as gay serial killer Aileen Wuornos in Monster. Buffed up and unglamorous, Theron may not have been an obvious choice, but the actress devoured the role full on. Proving she can step outside a glamorous box was only part of her desire to make the film. "Don't think all of it is that, but I do think it is a little bit like climbing Mt Everest. Why do people do that? I think we want to challenge ourselves to see what we are capable of. I think actors tend to do the same thing. I think it's that sportsmanship of "How far can I push myself?" There is also a sense that Hollywood can take one more pretty face a lot more seriously than before. "When this came along -- and I know it sounds like 'Yeah, right, that's for sure. That's what you tell everybody,' I didn't quite know where we were going to go with what she was going to look like physically. It wasn't like, when I said yes, I knew that I was going to look that and therefore went 'Well that would be good because then people will see me in a different way'..." Monster is an independent film that is grisly and depressing at times and, for Theron, there is still a certain vindication to come from the industry has seen more than its share of beautiful ex-models taking star turns. "I'm getting really honest feedback, which I really like. We do live in a world where people come up and go 'I'm going to tell you straight, I didn't think you had this in you' and that's really nice to know. You really feel that people are honestly giving you feed-back."

Theron stars as the famed Florida-based serial killer who at various times tried to get her life straight but society wouldn't allow it. Her love affair with Selby [Christina Ricci] gives her hope. Theron devoured as much as she could on Aileen, but fell short on meeting her –she was executed just days prior to filming. Had Theron met her, she says she wouldn't know how to talk to a woman who had remained so unrepentant. "I think a day before she was executed we talked about it briefly because Patty wrote to her a couple of times and they corresponded to each other, so Patty said 'We should figure out a way for you guys to meet'. Then when she was executed it was the kind of thing where that was done. I couldn't kind of stay in that path and dream about what I could ask her. It was really, how do I now get the information another way."

Theron points out that it is hard to make a 'sympathetic' serial killer movie, citing others such as Badlands. "I felt that the other side to her story held a lot of empathy and that it is sometimes hard to look at those things because she had done such horrendous things in her life. I don't think in this movie we try to oversee that or forgot about that but we stayed very true to the fact that she killed innocent people and I think that that's what people have a problem with. But I really believe, otherwise I wouldn't have done this movie, that in that greater truth of her story and watching that, you do get to a place of empathy and that to me was the most important thing.

Theron is so passionate about Monster, that the Golden Globe nominee would barely discuss anything else, even other projects. Try getting her to talk about her role in the new Peter Sellers biopic with Geoffrey Rush and she does her best to be as brief as possible. "I only had a few days on it" or "I'm a huge fan of Sellers" or "I loved working with Geoffrey." Even trying to broach the subject of an Oscar nomination is met with a certain disdain, though she finally admits that the ultimate prize "would be nice. I mean the immediate response is like 'Wow'. It's the kind of thing that -- look nothing has happened. We can talk about it all we want but I have so much going on in my life, and I'm really proud of this movie, I want to get it out there. I want people to see it and that's really the first and foremost thing for me right now. All of the other stuff is really nice because you never know when you start a movie how it is going to end up. So that, to me, is just another extension of people to actually responding to the movie," she says.