After he was sent the script for the fact-based thriller, he said getting on board was a no-brainer.
"Talk about a page turner, you know, I couldn't wait to get to the end," Affleck said. "I was terrified, I was tense, I was nervous, it was a thriller, and yet, it was really funny."
Affleck also stars in the film, which goes behind the scenes of the Iran hostage crisis and looks at a life-or-death operation to rescue six Americans. The character he plays is a CIA operative who comes up with a desperate -- and what some called crazy -- scheme.
Affleck's on-screen alter ego led a life filled with risk-taking, and Affleck said he could relate.
"I've always wanted to try to take a big swing, and sometimes I've missed. But I believe that failure is a function of risk," he said. "I try to take a big crack at things, and maybe the next movie, like it'll be a total brick, and you'll come in here and pretend to like it, but I want to keep taking risks."
While it's not easy to juggle more than one job on a movie set, Affleck says he's looked to those who came before him for inspiration on how to do it right, including Clint Eastwood, Robert Redford, Warren Beatty, George Clooney, Kevin Costner and Mel Gibson.
"There's a fair chunk of people who've been able to do this," he said. "That model is part of what made me feel like, OK, maybe I can do this too."