The original story of The Little Mermaid is about a mermaid who dreams of some day becoming a human. Ponyo is based on the same theme, but this time it’s a goldfish called Brunhilde who dreams of becoming human. This isn’t Disney computer-assisted animation as usual, however, but rather the amazing hand-animated world of Japanese legend Hayao Miyazaki.
By sheer effort of will combined with some magic stolen from her Dad, Ponyo sprouts arms and legs, transforming herself into a little human girl. She seeks out Sosuke, having fallen in love with him, and thereby disrupts the balance of magic, causing a tsunami that raises the sea level many feet in Sosuke’s town and threatening to destroy the world.