Robert Mackenzie is an Australian supervising sound editor, he is known for which critically acclaimed biographical war-drama film, directed by Mel Gibson and written by Andrew Knight and Robert Schenkkan?
Robert Mackenzie (sound engineer):  He is best known for his work on "Animal Kingdom" (2010), "The Hunter" (2011), "Lore" (2012), "Felony" (2013), "The Grandmaster" (2013), "The Rover" (2014), "Deadline Gallipoli" (2015), "Partisan" (2015), "Lion", and critically acclaimed war-drama film "Hacksaw Ridge", for which he received two Academy Award nominations at the 89th Academy Awards, Best Sound Editing and Best Sound Mixing . Hacksaw Ridge: Hacksaw Ridge is a 2016 biographical war drama film directed by Mel Gibson and written by Andrew Knight and Robert Schenkkan, based on the 2004 documentary "The Conscientious Objector".
Hacksaw Ridge