Bradley Cooper on working with director Clint Eastwood

How did Bradley Cooper pull off those intense rooftop sniper sequences in the Oscar-nominated film "American Sniper"? Cooper told 60 Minutes that Clint Eastwood was right next to him, off-camera, talking him through every step.

"He's close by," says Cooper. "There's no way I could've done what I did without that. There's just no way. I mean, if you have a guy like that with you in the trenches, telling the same story with you and you feel like he's got your back, basically, I just felt myself to be so much freer--as opposed to him being 20 feet away underneath a tent with a monitor, telling somebody else to come out and tell me something. That's gold, man-- that's gold for an actor to have your director be right there."

Earlier this year, Cooper and Eastwood sat down together for a joint interview with Steve Kroft for this week's episode of 60 Minutes. At the time of the interview, Eastwood was 84.

"I tell you what made me angry," Cooper said, "when people would constantly say, 'Wow, 84 years old, huh? Amazing he could still do it.' And I think, 'No dude--Because he's 84, he made a movie like that.... That's why he was able to tell this story with zero ego. You never feel, at least when I'm watching the movie, that you feel the filmmaker's hand trying to dazzle you with the cinema of it. He really just sat back and said, "This is a character study, and we're going to have this guy fill the frame and I'm going to trust that this guy is compelling enough to tell the story. I was so relieved when I saw the first cut."

"American Sniper" footage courtesy of Warner Bros. Entertainment Inc.