In recent history, atrocities have often been committed in the name of lofty ideals. One of the most disturbing examples took place in Cambodia's Killing Fields, where tens of thousands of victims were executed and hastily disposed of by Khmer Rouge cadres. Nearly thirty years after these bloody purges, two journalists entered the jungles of Cambodia to uncover secrets still buried there.

Based on more than 1,000 hours of interviews with the top surviving Khmer Rouge leader, Nuon Chea, "Behind the Killing Fields" follows the journey of a man who began as a dedicated freedom fighter and...