The words "My Lai" are seared into our memories of the Vietnam War but few know what really happened in the small Vietnamese village on March 16 1968. Now drawing on 400 hours of recently discovered audio recordings and new interviews with participants eye witnesses and investigators the complete story can finally be told about one of the most shocking atrocities in modern times-and about lesser-known acts of remarkable courage. Academy Award-nominated filmmaker Barak Goodman reexamines how an ordinary American infantry unit came to murder more than 300 unarmed Vietnamese civilians how a handful of their fellow soldiers tried heroically to stop them and how U.S. officials struggled vainly to keep the world from hearing about My Lai.