Join prolific rock climber Alex Honnold on his daring attempt to set a world record by free soloing a trio of harrowing cliffs without any safety lines. One of climbing's most decorated prodigies, Honnold has set his sights on the daring, ambitious and dangerous goal of scaling the faces of Yosemite National Park's Triple Crown: Mt. Watkins, The Nose and the Regular Half Face of Half Dome. And he plans to do it all in under 24 hours.