In April 2003, avid mountaineer Aron Ralston ventures out for a solo hike in the breathtaking Canyonlands National Park in Utah, failing to notify anyone of his whereabouts. During his journey, he encounters two lost hikers, Kristi and Megan, whom he helps by providing directions. As they explore an underground pool together, they create fun memories, and the girls invite Aron to a party the following night, which he respectfully declines, opting to continue his adventure alone.
As Aron navigates the narrow confines of Bluejohn Canyon, a frightening incident occurs when an 800-pound boulder he is precariously hanging from suddenly shifts, brutally trapping his right arm against the canyon wall. Struggling with desperation, he attempts to free himself but quickly realizes he is utterly alone. To bolster his morale, he begins recording a video diary on his camcorder while he chips away at the boulder with a pocket knife. Sadly, the very knife that serves as his only tool slips from his grasp, forcing him to resort to using only his bare feet and a small branch to retrieve it.
Over the agonizing span of five days, Aron meticulously rations the scant food he has left and his remaining 300ml of water. He finds himself battling the cold at night, and when water becomes a distant memory, he reluctantly resorts to drinking his own urine. Ingeniously, he attempts to fashion a pulley using his climbing rope, hoping to lift the boulder, but his efforts yield no success.
As hours turn into days, the weight of isolation takes a toll on Aron, leading him into a dark realm of despair and hallucinations that revolve around escape and memories of his past – including glimpses of his family and his former girlfriend, Rana. One haunting vision presents the joy of the party he was invited to, overshadowed by the stark realization of his isolation – the folly of not informing anyone about his plans. However, on the sixth day, a vision of his future son ignites a fierce will to survive and push through the torment.
Drawing upon his resourcefulness, Aron improvises a tourniquet using CamelBak tube insulation, tightens it with a carabiner, and in a gruesome but necessary act, breaks his arm bones using torque principles. With steely determination, he meticulously employs a multi-tool to slowly amputate his trapped arm. After securing the stump to prevent exsanguination, he captures a poignant snapshot of the boulder that subdued him, before utilizing his climbing skills to rappel down a 65 ft (20 m) rock face.
As fate would have it, he discovers stagnant rainwater during his descent, which he consumes out of dire thirst. Soon after, he spots a hiking family in the distance and desperately calls for their assistance. They provide him with water and promptly notify the authorities, leading to his rescue by a Utah Highway Patrol helicopter, which whisks him away to a hospital for treatment.
In a poignant textual epilogue, it is revealed that years later, Aron has married and welcomed a son into the world. He continues to pursue climbing adventures, always leaving detailed notes for his family outlining where he has gone, ensuring that he never again faces such a perilous ordeal alone.
