Everest’s a hill and K2’s a stairway compared to what’s called “Big Wall” climbing, and India’s Mount Meru (aptly dubbed the “Shark’s Fin) is the biggest wall of all. This madness entails ascending sheer and usually frigid granite faces, without the luxury of Sherpa or porters, sleeping for weeks in a hanging tent. What these three elite climbers did is phenomenal. That they brought back images of such vertiginous grandeur even more so. Courageous or suicidal? Beats me. But the film’s examination of each climber’s motives and personal struggle raises it above mere X-treme sport. (90 min)