The physical requirements for the scene weren’t complicated. Bryan Cranston, who plays CIA manager Jack O’Donnell in director Ben Affleck’s hostage rescue drama “Argo,” had to walk from one office to another, and as laid out in a Los Angeles set late last year, a straight line ran from point A to point B.

But before Cranston took a step, Affleck pulled the actor aside and redirected him.

Iranian militants had just stormed the U.S. embassy in Tehran, and details about the 1979 takeover were muddled - the situation was chaotic, and O’Donnell’s demeanor had to reflect that. What’s more, O’Donnell had to deliver more narrative exposition than could possibly fit if he walked and talked without any detours. So Affleck plotted a zig-zagging path filled with barriers such as desks and chairs, giving the character not only the time to explain the event but also plenty of impediments to dramatize the pandemonium.

“It seemed kind of odd, but the director can inform the audience what the physical geography is,” Cranston said. “What it told me was that Ben was still telling the story.”

Opening today (see the ‘A’ review in TGIF), Affleck’s third film as a director (following 2007’s “Gone Baby Gone” and 2010’s “The Town”) won early acclaim from critics and audiences at the fall film festivals. “Argo” is already generating favorable mentions from all manner of awards prognosticators, and Affleck has been singled out for his work not only behind the camera but also in front of it - he stars in “Argo” as Tony Mendez, the CIA operative who invented the rescue scheme.

Yet the film, which is based on real-life events but goosed with fictional third-act suspense, is as much a stand-alone movie as the cap to a remarkable Hollywood comeback story.

Less than 10 years after dwelling in the industry’s punch-line fringes, owing largely to the disastrous “Gigli” and his relationship with costar Jennifer Lopez that branded the couple “Bennifer,” the 40-year-old Affleck has transformed himself into one of the town’s most sought-after directors. Like actor-directors Clint Eastwood and George Clooney, Affleck is determined to make intelligent crowd-pleasers, and his first two movies did just that.

Though more than a few directors are comfortable essentially remaking the same movie again and again, Affleck quite purposefully chose “Argo” because he’d never done anything quite like it. With a price tag of about $44 million, “Argo” is also one of the season’s more daring gambles, the kind of movie most studios stopped making in the last decade.

As Iranian militants stormed the U.S. embassy, six State Department employees narrowly escaped the takeover, hiding with Canadian Ambassador Ken Taylor. To bring the Americans home, Mendez had to concoct a plan that would allow the houseguests essentially to walk out and fly home in plain sight. Mendez’s epiphany was to have the six pose as a movie crew, and to sell the con Mendez created a fake movie called “Argo” and a bogus production company.

“I was so greedy to be a part of it,” said Affleck, who was a Middle Eastern studies major at Occidental College before dropping out to act and team with Matt Damon to win the original screenplay Oscar for 1997’s “Good Will Hunting.” “The screenplay was clearly written by somebody who had similar taste to mine, which wants to err on the side away from telling the audience what to think, and rather allow them to make their own determinations and insights.”

Chris Terrio’s script had been developed by producers Grant Heslov and Clooney, and the two had seen something in Affleck’s first two features that convinced them he was a wise “Argo” pick.

“They were not groundbreaking stories but they were really well told,” Heslov said of “Gone Baby Gone” (which brought Amy Ryan a supporting actress Oscar nomination) and “The Town” (whose Jeremy Renner was a supporting actor pick). Clooney said he was disinclined to say Affleck has grown as a director. “I’m not sure about ‘growth’ because that would imply that his first two films were somehow lacking,” Clooney said. “I loved them both.”

Just because Affleck is now focused on directing doesn’t mean that he’s abandoned acting. Far from it. He feels an almost equal duty to be on screen when he’s behind the camera, fearing that otherwise he would disappear from the radar.

“The thing about directing is that it takes a year or two years to do, and if you’re not in a movie, Hollywood’s kind of like dog years. ‘It’s been forever - what happened to him, we haven’t seen him in anything,’” said Affleck, who stars in Terrence Malick’s “To the Wonder” and has a part in next year’s gambling drama “Runner, Runner.”

As a director, he’s more than a little obsessive about his work. He will occasionally go back and tinker with his editing of “Gone Baby Gone,” “The Town” and “Argo,” asking whether he could have made better cuts here or there. “I get neurotic about it - did I make a mistake there? Should I have done something else here?” he said.

But for all of his self-examination, Affleck isn’t sure how he would define his filmmaking style. What he does know, however, is that he is drawn to certain ideas.

“I hope the consistent theme is that the characters are complicated and that there’s nobody who’s particularly good and there’s nobody who’s totally bad,” he said. “The idea that there’s complexity to the character of a man or a woman is really interesting to me. Tony Mendez is interesting to me - he’s got failings. You see people’s weaknesses as much as their strengths, and then you get surprised by what they do. Or at least I do.”