Mel Gibson got his start in a war movie, and now he’s decided to make another one: Hacksaw Ridge, Gibson’s latest directorial effort, tells the story of Desmond Doss, a conscientious objector in World War II who refused to carry a weapon because of his religious beliefs. Thursday brings the first trailer for the film, which stars Andrew Garfield as Doss, and guys like Vince Vaughn and Sam Worthington as the mean soldiers who eventually come to appreciate him.