Maggie McKenna loves the sea. One of the best things about living in Galveston is being able to swim in the gulf and walk along the seashore with her father. Maggie wishes those special times with her father would never end. She knows she's wrong to be jealous of the new baby that's coming, but the bad feelings keep building inside her like a threatening storm. She even resents the time her father spends with Felipe, the Mexican boy from the orphanage who does odd jobs around the house.
When her father has to take her mother to Houston to see the doctor, Maggie is left behind to struggle with the jealously that is sweeping away her common sense. But soon she is facing the battle of her life when the very sea she loves, stirred up by one of the most powerful hurricanes of the century, ravages Galveston, destroying homes and lives in a powerful and violent flood. Her only chance at surviving through the night is to join forces with Felipe as they try to ride out the storm together.