Kristen Stewart Does Her Own Singing In ‘Runaways,’ Joan Jett Reveals

'She's an actress of weight, honesty, integrity and depth,' Jett tells MTV News at 'New Moon' premiere.

LOS ANGELES — It’s no secret that Kristen Stewart has become very, very famous over the past year. It’s also no secret that she takes her craft very seriously, respects a lot of artists who have come before her and holds a special place in her heart for Joan Jett.

At Monday’s (November 16) “New Moon” premiere , the legendary rocker was a special guest on the red carpet, walking just a few feet ahead of the A-list actress who has spent the past few months sharing her short, spiky haircut for “The Runaways,” an upcoming film about Jett’s all-girl ’70s punk band. Stewart told us the film is going to aim for a Sundance premiere in January, and Jett revealed much more about the pair’s friendship and whether KStew will be performing her own music in the flick.

MTV: So, Joan, are you a “Twilight” fan?

Joan Jett: I’d obviously heard about the movie, but before she was cast as me, I hadn’t seen it. Of course, when she was cast as me, I wanted to see the movie, and I’ve seen everything she’s done. I really enjoyed it. I thought it was really entertaining, and I’m excited that she was cast as me in “The Runaways.”

MTV: Kristen told us awhile back that she wasn’t sure if the director would dub in her singing voice and guitar. Will we hear her or a studio musician?

Jett: She’s singing. She’s definitely doing the singing, yeah. And during the filming, she was playing guitar. We went through it. I showed her the positions that I play — because some guitar players will use different hand positions on the boards — so I showed her how I played it, and she picked it up really well. I’m a lefty, too — not guitar-wise, but in my handwriting. So she switched that up too; she was writing with her left hand. She really, really embodied it.

MTV: We know you and Kristen became very close. What kinds of questions did she have for you?

Jett: I don’t know that she had specific questions, so much as she just observed me a lot. We talked; I would talk to her. She didn’t really have to ask me. I’d just dump on her my feelings about the Runaways: what it meant to me, what I thought we were trying to achieve, how I felt about girls playing rock and roll and stepping outside the box of what we were allowed to do in life, just that whole thing. And she’d listen to my accent and watch my body language. She’s an actress of weight, honesty, integrity and depth, and she’s very serious. She takes it as art.

MTV: Tell us about the first time you saw Kristen with that signature Joan Jett haircut.

Jett: I had a big smile. I thought she looked great. She really wore it well, with her body and the way she carried it. It was [weird]. It was like looking at a little sister.

MTV: Will you have a cameo in “The Runaways”?

Jett: No, I didn’t want to.

MTV: You became famous as a teenager, and so did she. Has she come to you for any advice on how to handle it all?

Jett: We did have discussions about life, you know? I think she’s got a great head on her shoulders, and she’s dealing with it just fine.

MTV: We know that you and Kristen spent New Year’s Eve together last year. What was that like?

Jett: We met on New Year’s Eve. I was doing a show up in Seattle. She flew up to watch the show, right after she was cast. We sat around, and that’s when I told her all about the Runaways and what it meant to me. She came to the show, saw the soundcheck.

MTV: Now that she knows how to play, would you ever invite Kristen up onstage during a show to jam with you on “Cherry Bomb”?

Jett: If she would do it, yeah. In a heartbeat. But I think she takes it all so seriously that she might not feel comfortable doing it. That’s just a guess — but maybe someday.

Check out everything we’ve got on “The Twilight Saga: New Moon” and “The Runaways.”

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