The son of a sailor, five-yr old Sosuke lives a quiet existence on an oceanside cliff with his mother Lisa. One fateful day, he reveals a stunning goldfish trapped in a bottle on the seaside and upon rescuing her, names her Ponyo. But she is no regular goldfish. The daughter of a masterful wizard and a sea goddess, Ponyo uses her father's magic to transform herself right into a younger woman and speedy falls in love with Sosuke, but the use of such powerful sorcery causes a risky imbalance in the world. As the moon steadily attracts nearer to the earth and Ponyo's father sends the sea's mighty waves to locate his daughter, the two youngsters embark on an adventure of a lifetime to store the arena and fulfill Ponyo's goals of becoming human.