Question: The 71st annual Venice International Film Festival took place in Venice, Italy between 27 August to 6 September 2014, Joshua Oppenheimer, won the Silver Lion Grand Jury Prize for which 2014 internationally co-produced documentary film, about the Indonesian killings of 1965–66?
Sentence (from "The Look of Silence"): The film is a companion piece to Oppenheimer's 2012 documentary "The Act of Killing".
Relevant evidence: No