In 2003, teenager Bethany Hamilton lives in Kauai, Hawaii with her parents Tom and Cheri, and two brothers, Noah and Timmy . All aresurfers, but she and her best friend Alana Blanchard have grown up with a passion for the sport and enter a competition. Her church youth ministry leader, Sarah Hill, is disappointed when she has to withdrawfrom a planned missions trip because of the contest.
Bethany and Alana place first and third, respectively, while the second place winner, Malina Birch, proves to be resentful. Bethany invites bothgirls up on the winner's box with her, but Malina ungraciously refuses. The Rip Curl surfwear company offers to sponsor her and Alana in competition.
The night before Halloween, Alana and Bethanysneak off with some friends to go surfing. Later while Tom goes to the hospital for knee surgery, both girls go surfing with Alana's father Holt and brother Byron. As Bethany dangles her left arm in thewater, a tiger shark appears out of nowhere and sinks its teeth into it, biting it off near the shoulder. Holt gets Bethany out of the water and puts a tourniquet on her while Byron calls 911. Anambulance meets them on the way to the hospital. Just before starting Tom's knee surgery, Dr. David Rovinsky is called to the emergency room to treat Bethany. She has lost her left arm, along with 60% ofher blood and he calls her survival a miracle.
Bethany's injury disqualifies her from the Rip Curl photo shoots, but she wishes Alana well. Rip Curl is supportive of her as it's executive providinga prosthetic arm that is cosmetically perfect and has bendable joints. Bethany angrily rejects it when she learns it will not help her surf. The onslaught of paparazzi also proves to be a great strainon her family and their privacy. The family, however, bears no ill will towards the Blanchards for taking her out to the place where she was attacked, and Cheri even tells Holt that she is grateful...