AFP - Actor-director Ben Affleck's latest movie tells the incredible story of Hollywood's role in an attempt to get a group of US diplomats out of Iran during the 1979 hostage crisis.

"Argo," Affleck's third film behind the camera, is set against the backdrop of the Iranian revolution and the international standoff in which 52 Americans were held in Tehran for more than a year.

The subject matter has clear topical resonance: the hostage crisis helped eject Jimmy Carter from the White House, and President Barack Obama, battling for re-election, is now facing pressure over attacks on US missions abroad.

But the 40-year-old Hollywood star says it was never his intention for the film -- produced by George Clooney and out this weekend in North America, less than four weeks before the November 6 election -- to be caught up in politics.

"It was always important to us to let the movie not be politicized. We tried to make it very factual, fact-based, because it was coming up before the election in the US, when a lot of things get politicized," he said.

The real-life story -- which was classified for years, and only became public in 1997 -- starts with the US embassy in Tehran being seized by revolutionaries, who went on to hold 52 Americans hostage for 444 days.

The Democratic Carter's mishandling of the crisis led to his defeat by Republican Ronald Reagan the following year.

As the mission was stormed, a handful of diplomats managed to escape through a secret exit and took refuge in the Canadian embassy. They were out of Iranian hands, but the next question was how to get them out of the country.

Central Intelligence Agency (CIA) officer Tony Mendez proposed a solution, which at first seemed far-fetched, but was eventually accepted.

The idea was to mount a fictitious Hollywood science fiction movie production, ask Tehran for visas to scout for filming locations -- and then get the diplomats out of the country disguised as film crew members.

"When I saw the script, I couldn't believe how good it was," Affleck told reporters, presenting the movie in Beverly Hills ahead of its release.

"What struck me almost right away was that we had this thriller, and in equal measure this kind of comic Hollywood satire and this really sort of intricate real-life CIA spy story, all based on truth."

Affleck plays Mendez, a real-life former spy who was heavily involved in the movie's production and even makes a brief appearance on screen.

"It was really inspiring to meet Tony. He was steeped in this movie. It was Tony's story, Tony's point of view," said Affleck.

"He wanted to meet me at this old famous CIA bar in (Washington district) Georgetown, and he was telling me that it was where (CIA double agent) Aldrich Ames passed names of the American agents in Russia to his Russian handlers.

"When he told me that, it kind of sank in all of a sudden -- this was real, this was a real story about a real guy who worked in a real world where real lives were at stake."

"Argo" maintains a delicate balance of tone as it depicts the Iranian revolution and the violent embassy scenes while also showing how a Hollywood production is put together.

Affleck stressed the importance of historical accuracy.

"Naturally we wanted to be careful and judicious about presenting the facts and also stand firmly behind that, and say that this is an examination of this part of the world," he said.

"Just because this part of the world is undergoing tumult, doesn't mean you stop examining it or talking about it. I think that would be a bad thing."

[image via Shutterstock]