AUSTIN, Texas (AP) -- "Drinking Buddies" is a comedy about blurring the line between work friendship and budding romance. And when you work in a brewery -- and partake of your product as often as you can -- that line gets even blurrier.
Writer/director Joe Swanberg premiered his movie Saturday night at the South By Southwest film festival. Known for indie flicks with minuscule budgets, he brought his eighth film to the Austin gathering. It's also easily the biggest production, with a cast featuring Olivia Wilde, Anna Kendrick, Jake Johnson and Ron Livingston.
Walking the red carpet, Swanberg said he didn't feel extra pressure despite the more-lavish production.
"The film grew to its size really organically," he said. "There wasn't a concerted effort to make something bigger; it's just that this was a story that I wanted to tell and then, as the actors came on board, the budget grew."
Though the plot was scripted, Swanberg had the actors improvise their dialogue so that the audience could "see real people coming through."
"You're not watching famous Hollywood actors playing roles, what you're seeing is their personalities shining through," he said. "They're still playing characters, but they're bringing a lot of themselves into it."
Wilde said she so relished making her lines up as she went along that "Drinking Buddies is the highlight of her career so far.
"It's the thing I'm most proud of," she said. "I feel that I devoted myself to this in a way I've never done. Improvising the entire film meant that I was constantly creating."
Wilde and Jake Johnson of TV's "New Girl" play colleagues at a Chicago brewery whose close friendship teeters on turning into something more -- even though both are in relationships with other people.
Kendrick, who garnered an Oscar nomination for best supporting actress for "Up in the Air" and also starred in "Pitch Perfect" and "50/50," plays Johnson's girlfriend. Livingston, of "Office Space" fame is involved with Wilde. But another star of the movie is beer, with bottles and glasses and plastic cups of it being swigged from copiously throughout.
The movie features few characters -- though Swanberg himself makes a cameo -- and the dialogue they share often feels spontaneous. That left a packed-house crowd at the Texas capital's stately Paramount Theatre laughing early and often on the festival's second night.
"It's a different muscle," Livingston said of improvising. He added of Swanberg: "He'll go without a net. He's not afraid to change the story as we go."
Johnson said he came of age improvising on stage and continues to do so at times on his television show.
"Joe knew what he wanted so it wasn't free form," Johnson said. "It was very disciplined improv."
Swanberg lives in Chicago and filmed on-location at breweries there. An avid home-brewer, he said he picked up more than a few choice tips during shooting.
"Making a movie in a brewery," Swanberg said, "that's about the greatest thing I could imagine."
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