After losing her mother, the medical student Nancy dumps the medical school in Galveston and travels to Mexico, hitchhiking to a hidden beach that her mother loved when was young. She brings a backpack and a surf board to surf and she meets two surfers that warn about the low and high tides schedule. They leave the sea, but Nancy decides to stay a little more. When she sees a dead whale floating on the water, she swims close to the animal and is surprised by a white shark. She is bitten on the leg and uses her medical knowledge to survive on a rock. But the high tide is coming and she is under siege of the ferocious shark.—Claudio Carvalho, Rio de Janeiro, Brazil