Among the most important documentaries ever made, The Thin Blue Line, by Errol Morris (Gates of Heaven), erases the border between art and activism. A work of meticulous journalism and gripping drama, it recounts the disturbing tale of Randall Adams, a drifter who was charged with the murder of a Dallas police officer and sent to death row, despite overwhelming evidence that he did not commit the crime. Incorporating stylized reenactments, penetrating interviews, and haunting original music by Philip Glass (Koyaanisqatsi), Morris uses cinema to build a case forensically while effortlessly entertaining his viewers. The Thin Blue Line effected real-world change, proving film's power beyond the shadow of a doubt.