A riveting chapter in the life of world-class athlete Diana Nyad. Three decades after giving up marathon swimming in exchange for a prominent career as a sports journalist, at the age of 60, Diana becomes obsessed with completing an epic swim that always eluded her: the 110 mile trek from Cuba to Florida, often referred to as the "Mount Everest" of swims. Determined to become the first person to finish the swim without a shark cage, Diana goes on a thrilling, four-year journey with her best friend and coach Bonnie Stoll and a dedicated sailing team.