In the three-and-a-half years of his rule in Cambodia, more than a million people, a fifth of Cambodia's population, were executed or died from hunger and disease. A supposedly gentle, carefree land of slumbering temples and smiling peasants became a concentration camp of the mind, a slave state in which absolute obedience was enforced on the 'killing fields'.

Philip Short has spent four years travelling the length and breadth of Cambodia, interviewing surviving leaders of Pol Pot's Khmer Rouge movement and sifting through previously closed archives from China, Russia and Vietnam, as well as Cambodia itself. Here, the former Khmer Rouge Head of State, Pol's brother-in-law and scores of lesser figures speak for the first time at length about their beliefs and motives, as Philip Short traces Pol Pot's life from altruistic youth to become one of the twentieth century's most egregious political monsters.