The Khmer Rouge killed two million people. And then the killers melted into the Cambodian countryside, never brought to justice. And they're alive today - living in stilt houses above the very rice paddies that contain their victims!

It boggles my mind.

What did they feel about it? Did they realize what monsters they were? How is it nobody ever even tried to hold them to account for what they did?!

When I was on the Cambodia border trying to help the refugees fleeing the holocaust in 1979, these are the questions that filled my mind. The injustice of it all made my blood boil.

Now comes a courageous documentary called Enemies of the People that asks these questions of the very people who ordered and carried out the killings. It's the result of a decade of patient reporting by Thet Sambat, whose family was slaughtered by the Khmer Rouge. He spent years befriending those that held the regime's secrets until at last they trusted him enough to talk.

The result is harrowing journalism and must viewing for those seeking to understand the banality of evil. Sambat is a hero - his persistence and grace are inspiring. I urge you to watch it.