The Khmer Rouge slaughtered nearly two million people in the late 1970s. Yet the Killing Fields of Cambodia still remain unexplained. A young journalist whose family was killed by the Khmer Rouge spends a decade making friends with those who directed and perpetrated the Killing Fields. He obtains ground-breaking accounts from the most senior surviving leader, Nuon Chea, Brother Number Two under Pol Pot, who talks for the first time in detail about the killing of party members considered to be "enemies of the people". Sambath's remarkable work further uncovers a network of killers, now ordinary fathers and grandfathers, who implemented the policy of terror in the provinces. The confessions that emerge create a watershed account of Cambodian history. A personal journey into the heart of the Killing Fields, this film is heartfelt quest for closure on one of the darkest episodes of the 20th century.