An Americam army veteran grieves by the tombstones of his army company that died during World War I. Back home, he raises his sons in a pious setting and asks them to shun weapons. After a naughty fight turns awry, Desmond reads the Bible and vows not to harm another human in his life thereafter. Desmond then saves the life of a worker, experiencing a wholesome satisfaction in the process. In the hospital, he is smitten by a nurse, who he then dates. After the United States enters the Second World War, both sons enlist, adding to the ire of the father who despises his sons joining the Army. The rigorous regimen of training in the Army requires Desmond to clear his firearms training, but after a huge tiff with his seniors, his father, an old corporal, intervenes to save Desmond from being court-martialed and serve with the Army as a medic. They get posted to Hacksaw Ridge, Okinawa. A win there would ensure that the Empire of Japan surrenders to the Allied Forces. What happens thereon?