"Free Solo" is a documentary film that follows rock climber Alex Honnold as he attempts to climb El Capitan, a 900-meter vertical rock face in Yosemite National Park, without any ropes or safety gear. The film captures the physical and mental challenges Honnold faces during his preparation and the actual climb, showcasing his dedication and skill. The documentary also explores the relationships in Honnold's life, particularly with his girlfriend, Sanni McCandless, and how his passion for climbing impacts those around him. It highlights the risks involved in free solo climbing and the pursuit of personal goals against the odds.