Your first film, ‘‘The Act of Killing,’’ was a portrait of the perpetrators of the 1965 Indonesian genocide, in which perhaps a million people suspected of being Communists were killed. In your new film, ‘‘The Look of Silence,’’ you focus on the murder of a single victim, Ramli Rukun. What made his killing stand out? Ramli’s murder had witnesses. Tens of thousands of others in that region were taken to rivers and killed, their bodies left to drift out to sea. Ramli’s body was dumped on an oil-palm plantation. For survivors, talking about Ramli was a way of insisting that the genocide had actually happened.

‘‘Silence’’ focuses on Ramli’s brother, Adi Rukun, who was born after Ramli was killed. You tried in 2003 to make a film out of Adi’s quest to learn about his brother’s fate. What happened? Within three weeks, the Army threatened the Rukun family. Adi suggested that I try to film the perpetrators instead. When I approached them, they were immediately open and boastful about the worst details of the killings. It was as if I’d wandered into Germany 40 years after the Holocaust, only to find the Nazis still in power.

That led to the making of ‘‘Killing,’’ in which you encourage the perpetrators to re-enact their atrocities in the style of, for instance, Hollywood westerns. Some critics say this sensationalizes the genocide. I would say to them: The raison d’être of the western is to glorify genocide here in the United States — the slaughter of the Native Americans.

With the perpetrators still in power, how did you finally come to the conclusion it was safe to make this film with Adi? Because of ‘‘Killing,’’ which I had shot but which had not yet come out, I was well known for being close to the highest-ranking perpetrators in the country, including the vice president of the country and members of Parliament. This meant that the men Adi wanted to meet — his brother’s killers, who were regionally powerful but not nationally powerful — would have to think twice before physically attacking us. They did not want to offend their bosses. Of course, after ‘‘Killing’’ was released, many of these men now hate me.