Further reading: Alex Honnold’s explanation for why he risks his life daily

Vasarhelyi and Chin, a married couple, are no strangers to climbing. The last film they made together was 2015’s excellent Meru, which was about Chin’s efforts to summit Meru Peak in the Himalayas and the grander metaphorical meanings climbers can assign to such quests. Scaling El Capitan without ropes is something that has literally never been done, and it’s so complex that it requires Honnold to plan out every moment of the route by climbing it with ropes and safety gear, over and over again. That process means that Honnold, the filmmakers, and McCandless are acutely aware of the hazards ahead—every tenuous, unsafe foothold or crevasse.

Through it all, Honnold is unperturbed. Chin delves into the specifics of his life history, and even looks at a map of Honnold’s brain (his fear center is not dead, but it’s largely unresponsive to regular stimuli, a doctor says). But, again, Chin isn’t trying to solve the mystery of what might drive someone to do what Honnold is doing. The result is a documentary that’s fascinated with its subject without being reverent, one that’s beautifully photographed (the way that Vasarhelyi and Chin capture the scale of Honnold’s climb is stunning) without ignoring the horrifying consequences lurking if he fails.

Honnold exists in a community that’s besieged with death; all of the climbers he meets up with and talks to over the course of the film have a fatalistic air to them. But even within this group, Honnold is regarded as a risk taker. In Alone on the Wall, a memoir published not long before he began his first preparations for El Capitan, Honnold describes his mentality during a climb as “empty.” He’s aware of the danger—there’s not much room for recklessness in free soloing—but his success partly requires him to not think about his potential death and injury. Honnold isn’t robotic (he’s actually somewhat goofy, at times), but when confronted with a difficult question, like the future he imagines with McCandless, he shuts down rather than interrogate it further.

As Free Solo progresses, the bond between Honnold and McCandless grows stronger, enough to lure him out of his van lifestyle and into a home in Las Vegas (he approves because of the nearby climbing opportunities). But that only makes his plans for El Capitan that much scarier. Even Chin, Vasarhelyi, and their camera operators have to confront the possibility that, in trying to make their movie, they may instead capture someone’s final moments. It’s this profound, human tension that makes Free Solo such a gripping and rewarding documentary to watch.

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