When the American embassy in Tehran was stormed in 1979, six U.S. embassy employees escaped and took refuge with the Canadian ambassador. In doing so, they avoided being held hostage alongside the other embassy workers, who would be prisoners for more than 400 days; but they could not leave the ambassador’s house, and had no way to get out of the country.

“Argo” tells the unlikely story of the CIA exfiltration operation to get them out of the country under the pretense that they were a Canadian film crew in Iran to scout locations for a lavish science-fantasy film. In order to make this plausible, agent Tony Mendez (Ben Affleck, who also directed) must first go to Hollywood and set up a cover for them, working with special-effects artist John Chambers (John Goodman) and producer Lester Siegel (Alan Arkin) to create the trappings of a fake movie production.

This would be a silly premise for a movie, if it weren’t true. It would still be a silly premise for a movie if they hadn’t done such a fine job with it.

In addition to being the most exciting movie about going through customs ever made, “Argo” is a great historical-political thriller, drawing us into history at the outset and then keeping us trapped throughout the film in that terrible moment in time that was the U.S.-Iranian hostage crisis. History creates the tension for the story, so that characters need not be embellished too much; in fact, fundamentally this is a movie about some people who stayed in a house and then, eventually, got on a plane, without ever a shot fired or a punch thrown, yet the sense of peril and fear throughout is crippling. We see the world outside the doors falling apart as one bloody regime is traded for another, and feel the power and brutality of the crowds swirling through the streets of Tehran.

“Argo” is a movie of exquisite balance. Arkin and Goodman provide some levity, but that never overshadows the seriousness of the story, and likewise the phony science-fantasy film becomes a colorful thread woven through the exfiltration operation without distracting from the history or the real danger the characters faced.

Another fairly impressive balancing act that Affleck pulls off is depicting the violence of the Iranian revolution in such a way as to make it frightening without caricaturing or stereotyping the participants. Maybe this arose naturally from the keen sense of detail that pervades the film, but it might also be helped by the extensive filming that was done on-location in Istanbul, with Turkish extras—ever since Istanbul was Constantinople, the Turks have occupied a unique place between East and West, which might be just the lens necessary for a dramatization like this.

And while Istanbul might not be an ideal stand-in for Tehran, the on-location footage goes a long way in making the film fascinating to watch. The world itself is a great special effect, for anyone who cares to go out and actually film it.

“Argo” also has a lot of great beards in it, as well as some spectacular mustaches. Some of the mustaches strain credibility, but then over the end credits we get to see a series of original embassy employee photos matched up with movie stills, and damn did those men know how to rock a ’stache.

The end credits also reveal how many shots were recreated from real footage of the time, and if that doesn’t leave the audience believing this is at least a mostly-authentic story, we’re treated to a fairly meaty audio clip of Jimmy Carter talking about what a hero Tony Mendez was. That’s not quite a presidential endorsement of the film, but a movie this steeped in history almost deserves one.