Joshua Oppenheimer won the MacArthur Genius Grant in 2014, primarily off the back of his 2012 effort The Act of Killing, a brutal and genuinely disturbing masterpiece . The film was about the 1965 Indonesian military coup, the subsequent genocides in which over a million people were murdered and the nation that Indonesia became having been run by the men who committed these acts of killing. It was a film that asked the perpetrators of these acts to reenact them, all of whom did with a worrying glee, in order to help us understand the cultural mindscape of the nation…