A GOOD MOVIE, adventure or otherwise, has a "butterfly moment," in which the protagonist overcomes adversity to achieve a goal. In a mountain-adventure documentary it's one of the easier shots to get, since summiters are usually eager to celebrate for a rolling camera. Capturing the agonizing "caterpillar moment" presents a greater challenge. Brown has more experience with that than he'd like.

In 1999, Brown was filming an expedition up Tibet's 26,289-foot Shishapangma when an avalanche claimed the lives of his teammates, noted climbers Alex Lowe and Dave Bridges. Brown's first reaction after the accident was "not to film. But everyone agreed we might regret not getting everything. I had to search inside for a long time to come to terms with that." With the blessing of Lowe's widow, Jennifer, Brown eventually made Shishapangma: A Celebration of Life. "Film is a powerful medium," Brown said. "If you try to turn it into a spectacle to get an audience, it's a cheap shot toward these people's lives. But if you're respectful, you can tell a great story."

Though the stakes on our expedition were not nearly as high, we suffered plenty. On the second day, during the most technical part of the climb, Levine and I stood on a tricky 30-foot wall filming porters hauling 50-pound loads. Brown fired off instructions: "Look for good, tight shots of hands gripping the rock … Get the great face reactions … nerve-racked, concerned." It's difficult to ask a man climbing a steep wall with a sloshing portable toilet on his head to look into the camera so you can capture his pained expression. I missed the shot.

Brown peppered us with tips throughout the trip. In Arusha, he warned us not to cut our shots too short. "Hold them for ten seconds, and actually count to yourself. Make sure that you're getting shots long enough to use in the edit." He encouraged us to search for unique angles, establishing different foregrounds and backgrounds, and after my feeble attempt at the time-lapse, he offered guidance. "A four-minute time-lapse zoomed in on the most dramatic terrain you can find is the best,"?he said. "Wider shots tend not to develop fast enough, so you have to burn a lot of tape."

Later that third morning, as we climbed above 13,000 feet, Emeka became a reluctant passenger on a malady merry-go-round. What began as a headache had become acute renal shutdown—he couldn't urinate. A Gore-Tex-clad water balloon waiting to burst, he staggered into a shallow cave to retch. I pulled out my camera and, with it, a Faustian dilemma: Was I really going to film this? How would the postgame wrap go? "Emeka, you just vomited up your bladder—tell me, how awful do you feel?" He didn't wait for my resolution, and again I didn't get the shot. I still regret it.

The next day, our fourth on the mountain, as we climbed toward summit-night camp, I asked Ross to film me running uphill for my music montage. "Thayer, stop running!" Brown bellowed.

"I'm just trying to get the shot," I fired back. Extra exertion at this altitude, Brown explained, could cause acute mountain sickness and terminate my summit bid—fitting, perhaps, for an adventure parody, but not the ending I envisioned.

Two hours later, we finally arrived at camp, a scrap of flat ground at 15,859 feet. It was a desolate purgatory, with little sign of life save the fiery-orange lichen clinging to the rocks. Emeka's condition continued to worsen—he didn't know it yet, but he was developing a mild case of pulmonary edema, a potentially fatal buildup of fluid in the lungs—and I had a headache that felt as if a nail-studded timing belt was cinched around my skull. Levine was exhausted, staggering like a zombie. In his tent, Brown reflected on the beleaguered state of his students. "Today I was thinking, I wonder if climbing Kilimanjaro isn't a little bit stiff for film school," he said. "But it's adventure-film school. Might as well do something that's hard enough for the students to understand what it's like to work in these conditions."