“Hacksaw Ridge” gives shocking insight to the realities of bloody combat with an honest-to-God concern for peace and humanity.

It is not unusual for a brutally sober film about war to make a viewer feel like a pacifist afterward, but Mel Gibson’s directorial re-debut about a Medal of Honor recipient and conscientious objector P.F.C. Desmond T. Doss (Andrew Garfield, “99 Homes”) explores the politics of actually being a pacifist in a combat role.

The film looks at Desmond’s rough upbringing under his alcoholic Great War veteran father (Hugo Weaving, “The Dressmaker”) where he almost kills his brother in a fight and vows to never lay a hand on another person in anger. This, combined with almost shooting his father to protect his mother, makes Desmond a walking embodiment of the Ten Commandments, something his fellow Seventh-day Adventists take seriously.

The day Desmond saves the life of a child trapped under a car in his hometown is the same day he meets the love of his life, Dorothy (Teresa Palmer, “Message From the King”), he decides to become a combat medic and join the war like his brother and all his friends. The ensuing struggle to remain true to his pacifism and distaste for even holding a gun in a rifle company, Sgt. Howell (Vince Vaughn, “Unfinished Business”) and Capt. Glover, (Sam Worthington, “Everest”) that beats him bloody, begging him to quit, almost ends with a court martial before his father pulls some strings with a fellow Great War veteran in charge of the battalion to clear up the confusion and his prosecutors leave him to enter combat without a weapon.

Skipping several years, and two bronze medals for his service in Guam and the Philippines, Desmond and his company, now friends, earn one anothers respect and march up the beaches of Okinawa toward Hacksaw Ridge. The final stretch of the movie is an intense and visceral lesson on how the eponymous ridge got its name, with more gore and dismemberment than any other war film in memory, though no single instance is focused on for long enough to give pause. “Hacksaw Ridge” does not shy away from brutality to say the least.

What the film does avoid, however, is much of the nuance surrounding Desmond and his career beyond the legend of his heroic deeds on Okinawa. Saving the lives of 75 of his fellow Americans, and some Japanese, is shown somewhat in montage as a series of miraculous and divinely inspired moments. This narrative-focused and somewhat simplistic representation was preferred in other places as well, such as when Desmond gives blood just to see his sweetheart (who says he cannot give more than once), when in reality he gave blood multiple times per week in good will.

Many of these historical inaccuracies are admissible, however, considering the realities of his life were far more unbelievable. Anyone not aware of the actual Medal of Honor citation for Desmond, which included a shattered left arm from sniper fire and an additional two weeks on beyond the two days shown in the film, might have thought the abundance of miracles was pretentious.

Overall, the film is most powerful in its start and finish, with only a procrastinating plot involving Desmond’s training at boot camp to hold it back. This is where some overt moralizing takes place, possibly coming from director Mel Gibson’s super-conservative values. The success of “Hacksaw Ridge” is ultimately, genuinely and appreciatively indebted to veterans and their sacrifices.