In The Shallows, Nancy is a girl who is not having a good time, because her mother has just passed away. She does what she can to overcome the pain, and among the things she does to try to forget is to go surfing, a sport that calm her.
One day she goes to a secluded beach, in order that nobody bother her, to do sport and think. On that lonely beach is attacked by a white shark, although luckily manages to survive the attack.
Swimming reaches the beach and there he tries to recover from the scare and see if he has wounds. He has to return to dry land, but he realizes that the huge shark stands between the beach and the land.
Nancy is going to have to use all her ingenuity to try to reach land without the shark killing her, as she is waiting for her to finish what she could not finish in the first attack, turning Nancy into her food.