Even if you don't have any idea who Che Guevara is, you probably know what he looks like. His face has graced everything from t-shirts to bikinis to cigarette packs to beer. You know he's a symbol of ... something. But you're just not quite sure what.

So, who is Che Guevara? And how did that picture of him become so damned famous? Those questions, and other issues, are addressed in the excellent documentary Chevolution, which debuted at Tribeca on Friday.

In the documentary, producer/director Trisha Ziff and director Luis Lopez explore the Che phenomenon from all angles, including the revolutionary's early life, his fateful encounter with Castro, the Cuban revolution he helped make happen, to his life trying to foment revolutions in other countries. But it also examines how he crossed paths with photographer Alberto Korda, the fashion photographer/photojournalist who took the famous picture of Guevara that was the basis for the icon we know today.