Sundance 2015: Meet the Breakout Star of 'Diary of a Teenage Girl'

Peter Travers chats with the fest's "It" girl about her acclaimed coming-of-age film

In this installment of Off the Cuff with Peter Travers, the Rolling Stone movie critic talks with a "Sundance virgin" and the "Bel" of the ball: Bel Powley of the acclaimed film The Diary of a Teenage Girl. "I'm just glad it's with this film," Powley says her newfound rep as the "it" girl of the 2015 Sundance fest. "I think it's a really important film and I want people to see it."

The film, based in Seventies San Francisco, is about a teenage girl (played by Powley) who loses her virginity to her mother's boyfriend. "I think that female sexuality in teenagers isn't a subject that is addressed a lot at all. There are a lot of movies about teenage boys wanting to get laid and losing their virginity and discovering themselves," the 22-year-old Powley tells Travers. "It's kind of a taboo subject."

After reading the script, the title character resonated with Powley so much that she dedicated herself to scoring the role. "Young females can be very 2D characters: You're either the virginal princess waiting for your Prince Charming or, if you have a lot of sex, you're a slut," Powley says. "So this movie is breaking boundaries… It's a girl coming out and saying 'I've lost my virginity, I get horny, I want to have sex.'"

The Diary of a Teenage Girl also stars SNL vet and new Ghostbuster Kristen Wiig as Powley's mother and True Blood's Alexander Skarsgård as Wiig's boyfriend. As Powley tells Travers, she and Skarsgård rehearsed for two weeks with director Marielle Heller so their chemistry would be well-developed before Wiig arrived on set.

Check out our Sundance page for complete coverage of the 2015 festival.