In August of 1974, Frenchman Philippe Petit—not content with having walked a tightrope between the twin towers of both Notre Dame and the Sydney Harbour Bridge—decided to try his luck rigging a tightrope between the big daddies of all the world's twin towers, the World Trade Center.

James Marsh's new documentary brings Petit's feat to life—an accomplishment that is either breathtakingly stupid or brave. And while I'm usually skeptical of documentaries that switch between B-roll and interview footage, the B-roll in this case is so outrageously implausible that it's more than enough to keep any viewer gripped. If you suffer from vertigo, for example, this movie will make you feel sick. Hell, I don't, and it still did.

Then there's Petit himself, who, even 34 years later, is an electrifyingly overstated presence onscreen. He's like a French Robin Williams, always doing these irritating caricatures of a Hollywood Frenchman. ("Aye ave ze mind of a criminal!") But whatever: The guy walked 200 feet across a 1,350-foot-high wire, with no safety net. He's allowed to be annoying.

Petit was also aided in his attempt by an assortment of ne'er-do-well extras, such as stoned rock musicians, a loser who gave up at the 11th hour, and an inside man at the Trade Center. Their amusing interviews take one back to a more innocent time, when planning something intricate at the Twin Towers didn't necessarily evoke the specter of George W. Bush grinding out the word "terrrrrism."

For further interest, on top of the circus act itself is the film's investigation of what it means to do something truly groundbreaking and exceptional. After completing his walk, Petit, it seems, lost most of his friendships, his girlfriend, and perhaps, a sense of purpose. After all, how can you top something like that?