"Why do you climb Mt. Everest," journalist Jon Krakauer (Michael Kelly) asks his fellow expeditioners during an evening powwow at base camp in the new epic "Everest," about the 1996 disaster.

"Because I can," is one of the answers, and that's as close as Baltasar Kormákur's film comes to providing insight into what possesses men and women to subject themselves through a brutal climb through the "Death Zone," across treacherous terrain filled with frozen bodies and precarious crevasses, at an elevation where your body is leaking oxygen.

And that's enough, really. What more is there to understand about the need to conquer the unconquerable, perhaps the most basic and inherent of human impulses?

This movie isn't about armchair psychology. It's certainly not about the back stories of the men and women at the center of the ill-fated expedition famously chronicled in Krakauer's "Into Thin Air," the documentary "Everest" and elsewhere, though fair attention is paid to the characters and they're played by terrific actors ranging from Jason Clarke to John Hawkes, Josh Brolin and Jake Gyllenhaal.

It is an enormous endeavor, with 3-D imagery that practically thrusts you onto the snow-packed slopes and into the steep canyons.

The picture utilizes every bit of the expanded frame to provide an immersive experience. But that's combined with a real sense of brutality, evoking the forbidding nature of death on the mountain, with its sudden avalanches, changes in weather patterns and other significant dangers.

Kormákur and screenwriters William Nicholson and Simon Beaufoy achieve something more than sheer spectacle by showing us that people climb Everest not because they can or they're seeking simple adventure, but because they must.