A spirited adventurer and avid mountain climber, Aron Ralston, embarks on a solo expedition into the desolate canyons of Utah. Full of confidence and enthusiasm for the solitude and challenge of the outdoors, he leaves home without informing anyone about his destination. His journey quickly becomes thrilling when he befriends two hikers, Kristi and Megan, showing them a hidden underground pool before continuing on his adventure alone. Unbeknownst to Aron, this chance encounter will be his last human interaction before facing a grave challenge.

While navigating a narrow slot in the canyon, a boulder dislodges and traps Aron's arm against the canyon wall, leaving him immobilized. As hours turn into days, he exhausts his limited supplies and tries to maintain hope, recording video diary entries on his camcorder. Faced with extreme isolation, Aron reflects on his life, relationships, and the potential consequences of his driven yet solitary existence. The severity of his predicament becomes increasingly evident as he battles the elements, dehydration, and the onset of despair.