Brie Larson is everywhere at SXSW

— Sometimes it seems no film festival is complete without an “it” girl — a Parker Posey, Zooey Deschanel, Greta Gerwig, Brit Marling or Elizabeth Olsen to encapsulate the current mood. This year’s South by Southwest, which opened Friday, may already have one: Brie Larson.

The 23-year-old with a wise kid-sister vibe and smartly cute style sense appears in three features at the festival: “Short Term 12,” which premieres Sunday and marks her first leading role, as well as “The Spectacular Now” and “Don Jon’s Addiction” (both of which first screened at Sundance). If that wasn’t enough, she also co-directed and stars in “Weighting,” a short film about a breakup.

“She’s going to be the queen of South-by,” James Ponsoldt, director of “Spectacular Now,” recently declared, only partly joking.

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Larson seems a particularly good fit for the free-spirited vibe of South by Southwest, not least because she was previously in “21 Jump Street,” which played to raves at the festival last year. She’s had other roles in films including “Scott Pilgrim vs. the World,” “Greenberg” and the dark L.A. police drama “Rampart.” Originally from Sacramento, she was cast on the short-lived 2001 sitcom “Raising Dad” with Bob Saget and Kat Dennings and more recently appeared on the Showtime series “United States of Tara.”

In “Short Term 12,” she plays Grace, a young supervisor at a group home for at-risk teenagers close to her own age. The pressure of helping others forces her to make some tough realizations about herself.

“I was very aware I hadn’t been the lead before,” Larson said in an interview in Los Angeles ahead of the festival. Being front and center for the first time, she said, required her to shed the comforting philosophy that if one of her movies is “great, it’s bigger than myself, but if it’s not great, I’m not the reason. I’m usually not in enough that I could make something terrible.”

Taking on the lead, she added, “I discovered a new sense of confidence through this project because of the fact I had such a crazy workload.”

“Short Term” writer-director Destin Daniel Cretton said Larson brought intangibles to the production he didn’t anticipate. Working with the younger actors who play her charges — most notably Kaitlyn Dever, who also appears in “Spectacular Now” — Larson saw pieces of her teenage self, just as her character does.

“She was great when we were rolling the camera,” Cretton said, “but she was taking a leadership role behind the scenes as well.” “From the day we started rehearsals, she took on that role with the kids, which I honestly think was a huge part of the way the kids were on screen. ... Brie built a relationship with them on- and off-screen and was a leader of that group throughout the entire shoot.”

In “Don Jon’s Addiction,” Joseph Gordon-Levitt’s debut as writer-director, Larson does a lot with a little: She only has one line of dialogue but spends numerous scenes as the sister of Gordon-Levitt’s character watchfully taking in family meals while texting on her phone. At a “Don Jon” screening at Sundance, the audience erupted with applause when her character finally said her piece.

In “Spectacular Now,” she plays the ex-girlfriend of the main character, but rather than become his nemesis or fade from the picture, she maintains a wary friendship with him. Her character’s drive to get out of their small town places his lack of ambition into starker relief.

“There’s a more typical version of a quote-unquote teen film where her character would have been cast as, oh, the blond girl and would have had no dimension,” Ponsoldt said, comparing her performance to Cybill Shepherd’s in “The Last Picture Show.” “Brie offered a complexity and nuance to a role that could have been so much less. ... She’s a capital-A actor.”

In preparing for “Short Term 12,” Larson shadowed supervisors in a group home. Among the first things they told her was how they all had to learn not to take the emotional baggage of their work home with them.

“I ended up taking that into my own life and letting it not just be Grace’s philosophy but my own,” she said. “In the past I’ve been very into the falling part, very into the swimming in the dark, deep emotional water. ‘Rampart’ I really went into it and it took me three times as long to get out of that depression as it did to just do the scenes. I had to learn to give it my all and then go home and laugh.”

With three feature films at SXSW plus her own short, an appearance on an upcoming episode of the sitcom “Community” and roles in the upcoming comedy “Relanxious” and Peter Bogdanovich’s “Squirrel to the Nuts,” it seems like a big moment for Larson. Yet she is trying not to overthink it.

“If I feel like this is a big year, then I have to compare previous years or future years and I don’t really want to do that,” she said. “It seems so arbitrary what people latch onto. I feel like I worked really hard last year, and now I get to see how that pays off.”

mark.olsen@latimes.com

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