Alex Honnold has achieved almost all the exploits possible in the world of climbing. However, that is not enough for him. The young mountaineer decides to carry out one more challenge: to crown the peak of El Capitan, a hill with a height of 2,307 meters, without any kind of protection to help him in the process. Alex is aware that two things can happen: Either, thanks to his physical form, he manages to overcome the challenge, or he will embark on certain death. The documentary follows the training and climbing of Alex, and the reactions of his girlfriend or his friend, director of the documentary, to what Honnold is willing to do.