The exiled whistle-blower, as Stone told me, embodies traits and themes the director has been drawn to in more than a few of his films: Platoon, Born on the Fourth of July, Wall Street, JFK. Movies about idealistic (possibly naive) young men who see their principles tested and their sense of self transformed inside the belly of a beast—where the beast is one of the big institutions of American power.

Snowden, starring Joseph Gordon-Levitt as Edward Snowden and Shailene Woodley as his girlfriend, Lindsay Mills, is the 20th feature film Stone has directed. True to his almost compulsive record of courting controversy, Snowden takes on one of the most divisive Americans of the 21st century. "At first, I didn't want to make this movie," Stone says. "It doesn't lend itself to cinematic glory; it's a live situation that is always changing. But the more I thought about it, I knew I had to do it. I could not walk away."

"We would write our version of a scene," Stone says, "and then Ed would help us get it right."