“Hacksaw Ridge” (Summit) recounts the extraordinary heroism of Army medic Desmond T. Doss (Andrew Garfield) during the Battle of Okinawa in the closing days of World War II.

A committed Christian and conscientious objector who refused to bear arms, Doss was nonetheless eager to serve his country. He single-handedly saved the lives of more than 75 wounded soldiers while under constant enemy fire, earning a Medal of Honor, awarded by Congress.

Director Mel Gibson, working from a screenplay by Andrew Knight and Robert Schenkkan, presents his fact-based drama in two parts. The first probes Doss’ childhood and upbringing in rural Virginia, while the second unfolds on Okinawa, atop a jagged cliff nicknamed “Hacksaw Ridge” for the brutality of the Japanese offensive there.

 We first meet Desmond as a boy (Darcy Bryce) who is losing a fistfight with his older brother, Hal (Roman Guerriero). Desmond picks up a brick and strikes Hal, knocking him out cold.

Recoiling in horror, the boy fears he has killed his sibling. He hasn’t, but the incident shakes him to the core, and inspires his steadfast pacifism.

“To take another man’s life is the greatest sin of all,” says his kindly mother, Bertha (Rachel Griffiths), citing their beliefs as Seventh-day Adventists.

Fast forward 15 years, and both sons have enlisted, to the dismay of their abusive father, Tom (Hugo Weaving). A veteran of World War I, he knows firsthand the horror and futility of war.

But Desmond is keen to play his part, despite the misgivings of his fiancé, local nurse Dorothy Schutte (Teresa Palmer). “While others are taking life, I will be saving it,” he reassures her.

Needless to say, Desmond faces ridicule and beatings by his fellow recruits at boot camp, who regard him as a freak and coward. The platoon’s leader, Sgt. Howell (Vince Vaughn), and the company’s commander, Capt. Glover (Sam Worthington), make his life miserable, and lobby for his discharge.

But Doss holds firm, calling himself a “conscientious cooperator.” A military court rules that he may serve as a medic, and not bear arms.

Once on Okinawa, Doss proves his mettle and earns the respect of his platoon as he runs back and forth on the battlefield to remove the wounded. His nearly superhuman actions would seem farfetched were they not true.

As might be expected with Gibson at the helm, “Hacksaw Ridge” does not sideline Doss’ religious convictions, which are integral to his story and his performance on Okinawa. With Dorothy’s Bible in his breast pocket, Desmond utters the cry, “Please God, let me get one more,” as he repeatedly plunges back into the abyss.

References to baptism and the resurrection give “Hacksaw Ridge” a transcendent quality that draws comparison with Gibson’s “The Passion of the Christ.” As did that film, “Hacksaw Ridge” uses the pain and bloodletting it portrays to inspire viewers with a redeeming Christian message.

The film contains graphic war violence with much gore, brief rear male nudity, a scene of marital sensuality and considerable crude language. (L, R)