Cosme and Monica live with their children and grandchildren in Bahia de Kino, a fishing town in the northern State of Sonora, Mexico. They used to call themselves predators of the sea until one day they became unable to kill a sea turtle. Submerged in a crisis, they embark on a journey to try to save their way of life and of their fishing town through the creation of an environmental community group in charge of protecting sea turtles.