Bob Balaban has told how he and Bill Murray became buddies while filming together for new war comedy The Monuments Men.
The pair play soldiers helping to recover art stolen by the Nazis during the Second World War in George Clooney's new comedy, based on a true story.
Bob revealed that though he and Bill had worked together before, they really got to know one another playing bunk mates on the frontline.
He said: "We did feel like a team, and my character and Bill's character were together a lot and it was really fun.
"We had been in Moonrise Kingdom a couple of years before and we both have a part in Wes Anderson's new movie Grand Budapest Hotel, so we'd worked together a couple of times.
"But coming on location for four or five months, you really get to know people, and we were lucky in our case because you could come to hate each other, but we came to enjoy each other a lot - we had a great time."
George directed the film, which he also stars in with John Goodman, Jean Dujardin and Matt Damon. Bob revealed George made it look easy to do both.
He explained: "George Clooney was a very busy man during this movie. The logistics of filming were tremendous, and he was in most of the scenes as well.
"There are some wonderful actor/directors who do this all the time, but it requires a real special individual who can bifocate their mind basically. In one mind, he's judging, working and watching as the director, and in another mind he's his character and he can't be thinking any of those directorial thoughts while he's acting.
"And he's very good at doing that and very good at maintaining his cool. He was very good at hiding the sweat and the strain and once he got on set, he never looked like it was hard."
::The Monuments Men is in cinemas now.