A natural talent in the sport of surfing, teenager Bethany Hamilton (AnnaSophia Robb) loses an arm in a shark attack. Bolstered by the love of her parents (Helen Hunt, Dennis Quaid) and refusing to give up, she plans to return to competition, although questions about her future continue to trouble her. Upon seeing the devastation in Thailand caused by the 2004 tsunami, Bethany discovers a greater purpose: to make a difference in the lives of others.