Survival is not the supreme value, but it has a unique power to put other values into perspective.

We say, too often and unthinkingly, that we would “rather die” than do this or that. It is a salutary thing not to fear death, but there is nothing salutary about trivializing the precious gift of life — precious, not only to ourselves, but also to those left behind.

To return, as if from the dead, to family and loved ones … What would we not do? We would “move mountains” for them, we say — another unthinking phrase.

There are no moving mountains, not even one mountain. What if there was more than one? How many mountains would it take, snow-capped and treacherous, to come between you and your life?

What happens when we are really, irreducibly confronted with such stark realities? Most of us can only guess, or fear. A few have discovered in extremis what we hope never to have occasion to learn about ourselves.

Stranded: I’ve Come From a Plane That Crashed on the Mountains, a haunting new documentary about the infamous 1972 Uruguayan flight disaster, vividly explores the memories and experiences of a group of college rugby players who crawled out of a shattered fuselage on Friday, Oct. 13, to find themselves in a desolate, snowbound valley somewhere in the Andes, with no special gear or clothing — and virtually nothing to eat.

The 10-day trek of two of the survivors, 2 1/2 months later, across more than 20 miles of rugged, snow-covered mountain terrain, and the subsequent rescue of 14 additional survivors, captured the world’s attention. At first it was called a miracle; later, the eventual acknowledgement of the most shocking element of their story was sensationalized in lurid headlines that both vulgarized a dreadful necessity and trivialized the ingenuity, altruism and fortitude that made their survival possible.

Even today the incident is exploited for an exercise in bumper-sticker sports bravado (“Rugby players eat their dead”).

The story has been told before, notably in English Catholic writer Piers Paul Read’s 1974 book Alive: The Story of the Andes Survivors. Twenty years later, in 1993, the Disney-Paramount film Alive, directed by Frank Marshall, offered a semi-fictional take on the story, and there have been at least two documentaries and a cheap Mexican film. Two years ago, survivor Nando Parrado published his own memoir, Miracle in the Andes.

Documentary filmmaker Gonzalo Arijón and cinematographer César Charlone (City of God), who collaborated on Stranded, are both Uruguayans and childhood friends of several of the survivors, and Stranded is arguably the definitive retelling of the disaster, the 72-day ordeal and the immediate aftermath.

Blending interview footage with all 16 survivors as well as family members and others with evocative, effectively wordless reenactments, real photographs taken before and after the crash, and post-rescue footage, the film tells the survivors’ stories in their own conflicted, sometimes conflicting, words.

The filmmakers also return with some of the survivors and their families to the site of the crash, now called the Valley of Tears, and the harrowing mountain trek that led to rescue.

What the survivors reveal about their experiences offers unique light on what it means to be human. Some concerns and priorities cease to have meaning; money becomes paper, and ordinary social customs fall by the wayside.

Other attachments and affections persist, even as you discover that they no longer constrict your actions in ways you could scarcely have imagined. Questions of ultimate meaning, of God or blind chance, take on new urgency.

In the end, we can only hope, our perpetual preoccupation with self becomes irrelevant, and the common good becomes the sole priority.

Though the players were all Catholics and many were observant, the survivors offer divergent spiritual perspectives on their experiences. There are repeated images of hands gripping rosary beads, and some sang hymns as well as prayed.

One, Roberto Canessa, who describes losing faith in a God who could have allowed this catastrophe, nevertheless joins in the prayers. Like the atheist mountain climber in Touching the Void who describes the impression of a malign cosmic force toying with him, Canessa sees the crash as a kind of laboratory experiment with the players as guinea pigs.

Yet another survivor describes feeling closest to God at the moment of greatest vulnerability on the mountain; when the sun rises, he says, “it was as if God were coming to save us.”

Returning to the mountain decades later, with adequate food, clothing and shelter, he adds that he no longer feels God’s presence there the same way as when his life was on the line.

Religious categories became particularly charged when it finally became necessary to confront the inevitable. One survivor notes that it seemed especially “sacrilegious” to use the bodies of the dead without their permission. Another appealed to the Eucharist itself as a precedent for what they had to do: “Jesus gave us his flesh and blood to eat. It’s like holy Communion.”

This metaphor would be repeated to the press when it became necessary to publicly address the rumors of cannibalism — something that the players had been trying to avoid out of respect for the families, whom they wanted to learn the truth from them rather than from the media.

Despite press sensationalism, the players’ survival was much more than grisly pragmatism. Two of them were medical students who set broken bones and so forth, and the survivors developed techniques for collecting melted snow to drink, and later crafted a sleeping bag with fabric from plane seats and insulation from the tail.

Without rules or laws, the survivors shared everything equally, rotating the most sheltered sleeping areas as well as what they had to eat.

Like Man on Wire, another recent documentary of a 1970s event, Stranded makes effective use of unobtrusive recreation footage. Utilizing a high-contrast, strobe-like style, the camerawork simultaneously evokes still photography and the dreamlike quality of old but indelible memories.

Though many were appalled by the grim revelation of the players’ survival and felt that death would have been a better choice, the Catholic bishops of Montevideo, and later L’Osservatore Romano theologian Gino Concetti, confirmed what the rugby players had already concluded amid agonizing on the mountains: As the only viable alternative to starvation, it is legitimate to resort to the bodies of the slain in order to survive.

Paradoxically, the taboo against eating the dead, and the justification for putting aside the taboo, have the same source: the sacredness of human life.

Stranded is a powerful meditation on life and death, on why taboos matter, and why they are not always absolute.

Steven D. Greydanus is editor and

chief critic at DecentFilms.com.

Content advisory: Occasional objectionable language; disturbing subject matter; mixed religious musings. Might be okay for mature teens.