Joshua Lincoln Oppenheimer is an American film director based in Copenhagen, Denmark. He is known for his Oscar-nominated films The Act of Killing (2012) and The Look of Silence (2014), Oppenheimer was a 1997 Marshall Scholar and a 2014 recipient of the MacArthur fellowship.

The Act of Killing is a 2012 experimental documentary film directed by Joshua Oppenheimer, with Christine Cynn and an anonymous Indonesian co-directing. The film follows individuals who participated in the Indonesian mass killings of 1965–66, wherein alleged communists and people against the New Order regime were tortured and killed, with the killers, many becoming gangsters, still in power throughout the country. The film was mostly filmed in Medan, North Sumatra, following the executioner Anwar Congo and his acquaintances as they, upon Oppenheimer's request, re-enact their killings and talk about their actions openly, also following Congo's psychological journey facing the topic.