In Unbroken, Olympic runner and World War II prisoner of war Louis Zamperini doesn’t falter, not once. Not as he races around the track during the 1936 Summer Games in Berlin, not through the ear-shattering, airborne gun fight, not after his bomber is shot down into the Pacific, not after endless beatings and long stretches of starvation in Japanese prisoner of war camps.

And given the film’s title, you don’t really expect him to.

But a truly extraordinary life alone doesn’t necessarily make for an extraordinary film—or even a good one. Even if the audience walks away in awe of Zamperini's story as I did, Unbroken falls short of the epic war drama and sweeping testament-to-the-human-spirit it strives to be. Zamperini, who passed away in July at age 97, inspired the 2010 book of the same name by Laura Hillenbrand, the subtitle of which became the film's somewhat heavy-handed tagline: "Survival. Resilience. Redemption."

To make Unbroken, director Angelina Jolie got some help from Joel and Ethan Coen, who adapted the screenplay (there’s virtually zero imprint of their style on this film, which did not boast the most impressive dialogue). During the making of the film, Jolie became quite close to Zamperini, eventually coming to see him as a "father figure" and one of her "best friends." Her take on his life was that despite being so "average," he survived—a sure sign of hope for a world filled with human suffering.

This is where the trouble begins: The film doesn't exactly portray Zamperini, played by the superb Jack O'Connell, as average. Yes, he has humble beginnings—born of Italian immigrant parents, a target for bullies, prone to trouble making,  that are elucidated speedily through some well-placed flashbacks. But he's also clearly exceptional, fearless and superhuman in his ability to transcend pain, even torture. O'Connell endures tragedy after tragedy with a certain steeliness, jaw muscle clenched, his gaze frequently unflinching. He's also tender and selfless, whether he's taking beatings aimed at other inmates or mesmerizing his fellow soldiers with stories of his mother's Italian cooking when they're stranded for 47 days in the middle of the ocean.

O'Connell inhabits Zamperini, or "Louie," with surprising and admirable commitment, giving his character plenty of grit and, in moments far too few, a hint of mischievousness. One can't help but feel horror during the boat scenes, when O'Connell and his crew mates, played by the memorable Domhnall Gleeson and Finn Witrock, turn increasingly skeletal with sunken cheekbones, jutting ribs, cracked lips, sunburnt skin, and dazed eyes. That feeling of horror, which returns again and again thanks to the film's jarring realism, has little payoff when it comes to story and character. O'Connell is phenomenal as Zamperini, but the screenplay prefers to stun the audience with images of paralyzing bleakness, rather than digging past the surface of Zamperini's persistence.

Unbroken was not destined to feel this empty. It contained several promising threads that would have fleshed out the story were they given more attention— a brief glimpse into the Japanese propaganda machine; the existential weariness of being a prisoner of war (As one inmate tells Louie, “If we [the Allies] win, we’re dead”); the twisted psychology of "the Bird," the Japanese corporal (played by Miyavi) who preyed on Louie.

There's a delicate alchemy to the prestige formula of making the audience feel-good-via-feeling-bad. But the film's plain intention of celebrating triumph in the face of unthinkable hardship translates into 137 minutes during which the audience is forced to watch Zamperini swallow countless injustices of the body and mind. And at the film's end, comes swelling credits-music that seems to say, "Don't worry, everything turned out alright!" complete with an epilogue and footage of Zamperini running a leg of the Olympic torch relay in Japan. This disjunction, however well-meant, feels at best tone-deaf, at worst exploitative.

Unfortunately, the film doesn't work without that epilogue, that reassuring pat-on-the-back that indicates all the suffering Zamperini went through (and that we, the audience, witnessed) was for something. The two hours or so that preceded these last scenes offer no such hope, as if the film were touting endurance-for-the-sake-of-endurance. With this narrative failing, the film inadvertently makes a sad point: War is meaningful only as a monstrous, collective effort; at the individual level, there's often nothing to make sense of. In other words, there's no inherent meaning in adversity. It's a fine if depressing statement, but certainly not the one the film wanted to make.

The real story, the one told more fully in Hillenbrand's book, continues well after Zamperini returns home to his family at the end of the war. That story involves years of intense post-traumatic stress and alcoholism immediately following his return home and later, a turn to Christianity and inspirational speaking. One of the major themes of his talks? Forgiveness, or the last of that trio of values, "Survival. Resilience. Redemption." Viewers will see plenty of the first two—Zamperini’s will to live, his imperviousness. I'm left wondering how much more powerful and true the story could have been had Unbroken focused as much on the third.