Watch VoirFilms. “The Core” features climber Dean Potter during one of his greatest feats: the one-day ascent of El Capitan and Half Dome, two of the world’s most famous rock faces, in Yosemite. Throughout the documentary, Potter describes what drives him to undertake such epic, perilous, and daring projects, which have made him one of the most renowned climbers. “The Core” captures not only Potter’s profound reflections, but also the iconic beauty of the national treasure that is Yosemite.