Ben Affleck is wondering when he became "an a**hole" to other actors.
The star has made the successful switch from starring in front of the camera to directing movies, but admitted it has affected his friendship with fellow thespians.
He revealed that on the set of his new film Argo, which he directs and stars in, his co-stars felt they couldn't relax around him when he joined them after filming.
"I'm not one of the guys anymore," he told British magazine Shortlist. "I remember I was walking over to the house guests and I heard one of the guys talking about getting stoned - I think somebody had brought something into the house - and as I arrived everybody clammed up. I thought, 'When did I become this guy? What am I, the dad?' I'm an a**hole all of a sudden."
Ben also revealed why he hasn't worked with Matt Damon for a while.
The best friends wrote and starred in the Oscar-winning movie Good Will Hunting, but Ben revealed their friendship was hyped so much it became a distraction from their actual work.
"We wanted to have our own identities; this whole Matt and Ben thing was so strong it kind of upstaged whatever the movie was. I think it's been long enough now, so we're about to do this movie together called Whitey, about this famous gangster [Whitey Bulger] in America. Matt's going to play him and I'm going to direct," he said.
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