Marine Captain Brian Steidle is an unlikely hero. Not because he isn't brave; he has shown courage under fire. But Steidle's accomplishment is entirely unexpected; he is a soldier who is learning to change the world through peaceful means.

The subject is Darfur. The journey takes place over the course of 18 months. Steidle went to Sudan as an unarmed military observer working for the African Union. He left as a witness to what many believe is genocide in the western Darfur region, a conflict that has claimed 400,000 lives and displaced 2.5 million people. In the transformation from soldier to observer to witness and activist, we see a man at first confounded by his naiveté and then confronted by the urgency of a humanitarian catastrophe that he sees unfolding firsthand.

An everyman figure, Steidle is initially unequipped to absorb the horror around him. Like many, he would rather not engage with something so incomprehensible and terrible. But he does, and Annie Sundberg and Ricki Stern's (The Trials of Darryl Hunt) astonishing film journeys from Darfur to the United States, then to Chad, Rwanda, and finally the United States again. His odyssey becomes ours as the more than 1,000 photographs he took become evidence of a crisis that cannot be denied.