Cambodia's suffering spans so many decades and so many horrors that, for those who are familiar with the country, it takes a great documentarian like Steven Ozakaki to redraw the focus from the totality of events under Pol Pot to the individual realities of people who survived, and - in the case of the person who is subject of this film - who would seek to re-shape the narrative and even profit from it. I have never met Nhem En, but I did meet the late Vann Nath, who always asked for understanding of people like En. The photographer of S-21 represents all the maddening riddles of Khmer society. This outstanding film has a mercilessly clear focus on its subject matter, but leaves out a ringing editorial voice of denunciation. Instead, 'The Conscience of Nhem En' invites one of the functionaries of the most violent revolution of the century to create with his testimony all the evidence we need to draw our own conclusions about the banality of evil. The film's consideration is of universal truths about the delusions and catastrophic self-deceptions of dictatorships, and how, rather than learning the mistakes of the past, revolutionaries repeat them.