In a small town by the sea lives five year-old Sosuke, high on a cliff overlooking the Inland Sea. One morning while playing on the rocky beach below his house, he discovers a goldfish named Ponyo, her head stuck in a jam jar. Sosuke rescues Ponyo and keeps her in a green plastic pail.
Both Ponyo and Sosuke are fascinated by each other and promise to stay firm friends until Ponyo's father - once human, now a sorcerer who lives deep under the sea - forces her to return with him to the ocean depths. What follows is an amazing underwater adventure for all ages....