In this exclusive excerpt from Chasing the Light, Scarface screenwriter Oliver Stone finds himself caught between Al Pacino and director Brian De Palma.

In our Spring issue, we asked Academy-Award winning director Oliver Stone if film can make a difference in vanquishing the darkness and rot that pervades through the ages of humanity. Stone, whose Showtime documentary series The Untold History of the United States recently spawned an education project, is a veteran in the trenches of political and social justice. He offered us a sober call to arms from the frontlines.