Director of education; STAR TALK.
He copied newsreels from the late 1970s to make it look authentic and give some back story to the Iranian revolution and the CIA's fantastical plot to rescue six Americans from Tehran after their embassy was overrun.
He says: "I wanted to contextualise the movie so we weren't just starting out with bearded lunatics rabidly pulling STAR TALK bricks off a building.
"You understood the history, the long road that led to that moment. It was not to make any judgment, but simply to educate the viewer."
Ben has enjoyed a rollercoaster career, from the highs of the Oscar for co-writing Good Will Hunting to the lows of acting jobs like Gigli and Paycheck.
However, he says taking the plunge into directing has been his most hair-raising experience.
"Asking a lot of people to rally round you and work with you is tremendously risky. The potential for failure is great and you do it in front of everybody."
He is obviously a persuasive boss, getting his Argo cast to live together for a week as rehearsal for their roles, giving up all contact with the outside world.
"There was a lot of complaining about losing their phones. Ultimately, we stationed a PA outside their house in case an emergency call came and they'd go in. But the definition of what constituted one started shifting. Your girlfriend calling isn't an emergency!" Ben is set to direct best friend Matt Damon in a biopic about Whitey Bulger, a Massachusetts mobster and one of the FBI's most wanted fugitives for 12 years until his arrest in 2011.
"Everyone in Boston thought Whitey was in Ireland the whole time. Turned out he was in Santa Monica, down the street from my house. We're working on the script but we're very excited."