Joan Jett Says Kristen Stewart 'Nailed' 'Runaways' Role

'I found us to be really, scarily similar,' the real-life Runaway guitarist tells Interview.

When MTV News caught a screening of Kristen Stewart's "The Runaways" at the Sundance Film Festival in January, we came away impressed by how the 19-year-old actress "physically embodies the role [of rocker Joan Jett] and curses and growls as the part demands." What did it take for KStew to embody so movingly a real life '70s rock-and-roll icon?

A keen sense of observation, a willingness to study hard and simply good casting. That's how ex-Runaways guitarist Jett explained it in an Interview magazine story.

"I found Kristen to be through and through totally professional and just great to be around," Jett said. "I found us to be really, scarily similar, just in our physicality, the way we move through space."

Stewart and Jett first met on New Year's Eve 2008, when the actress came to one of the singer's concerts. The pair ended up spending the entire day together, and Jett opened up about everything she could remember from her time as a '70s rock pioneer.

"I just dumped on her about everything I could think about the Runaways — I mean, the good, the bad, and the ugly," she said. "I told her all that stuff and how much it meant to me. Then she went off to do 'New Moon,' and I didn't see her again until about two weeks before the 'Runaways' thing started. But she is so authentic. The thing that came through to me was that it was important to her to capture it. She really wanted to nail it."

"Runaways" didn't begin filming until June 2009, and in the months that followed their New Year's rendezvous, Stewart listened to all the band's music that Jett gave her, as well as tapes of the singer talking. But even all that studying wasn't enough. When they reconvened weeks before the shoot, Stewart trained her powers of observation on Jett.

"[S]he was staring at me the whole time," Jett said. "And I was fine with it, because I knew she was watching my posture, my mannerisms, everything I did, the way I hold my hands, just everything. And she really soaked it in. When we were hanging out together on set, it was like I had a mirror image. Even just sitting around, we'd do the same thing at the same time. It was just great — and it wasn't creepy. It was wonderfully special."

Check out everything we've got on "The Runaways."

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