Once, in my twenties, befuddled by a crush on a gorgeous woman who was a rock climber, I joined a beginners' climbing weekend in the Shawangunk mountains, with expert instruction by the Appalachian Mountain Club. On my first free climb, near the top, I slipped down the rock face and fell about fifteen feet. My last words, in case you're interested, were "Jesus Christ!" though perhaps not said with the proper reverence.

I was reminded of the event, which I'd tried for years to put out of my mind, when I finally caught up with the recreated documentary "Touching the Void," about the horrifying things that can, and in this case did, happen when you climb mountains. In 1985 two young British climbers, Simon Yates and Joe Simpson, decided to try the unclimbed west face of Siula Grande, a 21,000-foot mountain in the Peruvian Andes. A difficult near-vertical ascent through unstable snow and rock took them three days, but as they left the summit ridge they were blinded by a snowstorm and Joe fell, breaking his leg so badly that his calf bone was driven up through his knee joint. Working into the night, they figured out an arrangement whereby Simon would let him down on their rope, Joe would find a stopping place on his one good leg, and Simon would climb down to join him. Their plan was to repeat that until they got to the bottom. Except that, unable to see where they were, Simon had let Joe down to dangle over a crevasse, where he simply hung helpless in midair, in excruciating pain.

Now Simon had to make a choice: He was on unstable snow himself, he could not communicate with Joe, could not pull Joe up, could not, in fact, do anything to save him. He chose to cut the rope and save himself. When he did, Joe fell into the crevasse, and the rest of the film is the story of what happened from that point on. Since he in fact survived (to write the story as a book) we know how it comes out - but that in no way lessens the suspense or the impact of the film. It is breathtaking from beginning to end.