Kristin Stewart has acted alongside an impressive list of actors at the tender age of 18. After a starring role in Panic Room with Jodie Foster in 2001, she went on to earn a solid reputation as an adult actress with her performance in Sean Penn’s Into The Wild, opposite Emile Hirsch. That performance caught the attention of director Catherine Hardwicke, who cast her in the coveted role of Bella - a girl who falls in love with a vampire - in the film adaptation of the wildly-successful book Twilight. We caught up with Kristin the day after the film’s manic London Premiere.

EW: Were you aware of the book’s massive following before you were cast?

KRISTIN STEWART: I knew how important it was to a small group of people, I didn’t realise how widespread they were. I felt like one of them initially, but then I realised I wasn’t as crazy as them (laughs).

EW: Twilight had a better opening day’s Box Office than High School Musical 3. Was it difficult to make something that wasn’t ‘squeeky clean’ but still appealed to a teen audience?

KS: I didn’t see it as that. I mean, you’ve got one character that is 108 years old, but because a film feature young people, they say ‘oh it’s a kid movie now.’ When it started out, it didn’t have to ‘be’ anything. It had a big following, and people were writing about it, but I’ve done studio movies before and we were given freedom here. We didn’t have this frame we had to fit into. I mean High School Musical is great, it’s a different form of entertainment, but they have something that they’re supposed to be and we didn’t have that.

EW: Will you be back for a sequel?

KS: I believe we start at the beginning of next year. I usually only get to fall into character for, like, 6 weeks. I do little movies and typically they may never see the light of day, so there’s this huge grieving process afterwards. But here I get to follow her for an incredibly long time, or at least until the second one. So I’m very excited.

EW: Do you think it will be harder now that there is the first movie to live up to?

KS: The press may be a little tougher, but hopefully the process (of filming) will remain the same.

EW: Do you worry about typecasting?

KS: Well there’s a large group of people who will only ever see us as these characters, so I don’t really know. There’s no way to be sure. I guess the only thing you can do is try and do good stuff in between. If it was just Twilight for the rest of my life, as an actor I’d be quite miserable. I just got cast as Joan Jett in a movie, which is also quite different from Twilight.

Twilight hits UK cinemas December 19.

See Kristen and co-star Robert Pattinson at the Twilight UK premiere below