"If you fail as an actor, you fail by yourself," he frankly explains. "As a filmmaker, you're asking a whole group of people to trust you and if you don't succeed, you take them down the sinkhole."
Critics were divided on his helming debut, branding it 'a fluke' while others recognised this square-jawed pretty boy had skills. He duly proved them right with quality heist thriller, The Town and now completes a winning directorial treble with Argo, easily a frontrunner at next year's awards circuit.
Based on former CIA operative Tony Mendez's account of the rescue of six American diplomats from Tehran during the 1979 Iranian hostage crisis, Affleck (40) has crafted a pleasing mix of edgy nostalgia, attracting an ensemble troupe including John Goodman, Bryan Cranston and ` casting himself as shaggy-haired Mendez.
"When you're an actor, you are constantly looking for the good part. So the way I saw it, I was sleeping with the director, of course I was going to take the part of Tony. That's how low I stooped."
The crux of this engaging story is the means Mendez used to infiltrate a country in ruin after the deposition of the Shah.
"To fake a movie location scout in Iran, claiming the diplomats were film crew, it's the epitome of 'stranger than fiction'. It's something I had to work on. I would have regretted it so much if I let this one go."
Married to actress Jennifer Garner, mother of his three young kids under seven, the A-list couple alternate their film schedules so one is always there for the demanding brood. It's also the reason Ben missed the opportunity to direct the pilot for political smash, Homeland. "I'm kicking myself about that, but Jennifer was working so I was at home. Now I can't bring myself to watch it, it kills me."
Ben and Jen met on the set of comic-book caper, Daredevil, alongside a shaven-headed Colin Farrell -- a man Affleck brands, 'a force of nature' -- but they've yet to reconvene for a second stint on the big screen. "It's just not practical right now," he sighs wearily. "How is that supposed to work with the kids? Down the line in the future, yes, but family comes first now."
School runs and nappy changes won't get in the way of his first true love, Good Will Hunting co-star, and soul mate, Damon, as the pair will work for the the first time since '97's Dogma on a biopic of notorious Irish-American crime lord, 'Whitey' Bulger. The ruthless gangster ran Boston's Winter Hill Gang, responsible for 19 murders during the 1970s, landing him on American's Most Wanted List until his capture by police last year, aged 81.
"Matt's going to play Whitey, I'm going to direct and it's all go. Funny thing is, everyone thought that Whitey was hiding out in Ireland until he was caught, where it actually turned out he was in Santa Monica down the street from my house."
And while the movie won't give Ben the opportunity to shoot here, sounds like he'll certainly premiere in Ireland after the warm reception he got on the red carpet at the Savoy for the Dublin opening of The Town.
"Give me a red carpet in Dublin any day over anything in Hollywood. There, it's so stressed out, you're getting pushed along by a publicist to meet and greet this sea of people, all wanting five minutes.
"Dublin was a breeze, I found myself stopping and talking to people who were inviting me back to their house for tea. You don't get that anywhere else."
Argo is in cinemas from Friday