Whoa! Zach Galifianakis has apparently been working on his physique. The Hangover actor, who hasn't made an official public appearance since Oct. 2013, reemerged at a screening of Birdman Or The Unexpected Virtue Of Ignorance at the closing night of the New York Film Festival in New York City on Sunday, Oct. 12, looking significantly slimmer.

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At a press conference for the film, the funnyman explained why he hasn't stepped into the spotlight for some time.

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"Being a celebrity is s--t — it's dumb, and I'm not interested in it," he said. "I like to be an actor, and that's it. The blurred lines are, I think, man-made. I think celebrity is a man-made thing; it's not innate in us…I'd rather just do my work and go home and watch Lifetime."

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In an interview with The Hollywood Reporter, the 45-year-old added: "It's confusing to me — all of this is confusing to me. They oversell it like we're curing cancer, you know what I mean? I just think it can be gross sometimes, the way Hollywood congratulates itself all the time."