FRONTLINE reveals the untold story of what happened in Haditha, Iraq, where twenty-four residents were killed by U.S. forces in what many branded "Iraq's My Lai." With accusations swirling that the Marines massacred Iraqi civilians "in cold blood," the incident has led to one of the largest criminal cases against U.S. troops in the Iraq war. FRONTLINE investigates the harrowing moral and legal landscape the military faces in Iraq.