Directed by documentary filmmakers and married couple Elizabeth Chai Vasarhelyi and Jimmy Chin who are best known for the award-winning 2015 mountain climbing movie Meru, Free Solo is an extremely fascinating and visually arresting documentary that follows the rock climber Alex Honnold as he plans to climb El Capitan in Yosemite National Park using the free solo technique. Alex is a thrill-seeker who is regarded as one of the foremost free soloists in which he climbs cliffs by himself and without any ropes or other safety equipment; an extremely dangerous sport in which the smallest slip will result in certain death. Besides showing the actual preparations and the free solo climb that takes place on June 3, 2013, the documentarians, who are skilled climbers and outdoor enthusiasts themselves, also attempt to explore Alex’s personal life and background without really questioning why he pursues such a risky passion. Rather unexpectedly, Alex is a very quiet and somber individual who has difficulty expressing his emotions, and he really does not feel alive except when he is on a mountain. For several years and during most of the film, he lives out of a van and leads a very solitary life without many close friends or family members outside of the climbing community. Even when he talks about the deaths of fellow mountain climbers and free soloists that he knew fairly well, Alex rather nonchalantly brushes off their fates as part of the thrill. The tragic ends of these friends does very little to dissuade him from tackling the seemingly impossible task of making a free solo ascent of the notoriously difficult El Capitan mountain. The only obstacle that he faces is the pressure he feels from his new girlfriend who tries to help Alex transition into a more normal lifestyle and even encourages him to purchase a house in Las Vegas. Despite her trepidations, he goes full steam ahead and, in some rather harrowing sequences, he goes on several practice runs with the traditional safety mechanisms before the climax of the film in which he free solos the almost 3,000-foot sheer cliff. The filmmakers do an excellent job of presenting the spectacular yet terrifying climbs of Alex through the use of skilled mountain climbing cameramen and drones, all giving the thrilling effect that the viewer is actually there alongside Alex. At several points during his final climb, even the documentarians and crew members are petrified that they may be filming the final moments of their new friend Alex and so several of them have to look away. Overall, I found it to be one of the more gripping documentaries I have ever seen as a result of its effective ability to explore the largely unthinkable extreme sport of free solo rock climbing through the mesmerizing and quite frankly scary footage of Alex Honnold as he fulfills his daredevil passions.