This story’s main characters are a boy and a fish.
The boy liked to daydream. One day, he saved the fish dying and imagined the fish became a mermaid. They enjoyed a great time by playing music and swimming together, and loved together. He came back to take it and showed to his parents. However it was only fish to them. Police caught him because in his country, free imagination was banned, and forced him not to be able to imagine. He resisted strongly but at last he couldn’t remember it and could see only fish. He was greatly shocked and returned it to the ocean. Then he could become to see the mermaid and disappear into the ocean together.
I think that Osamu Tezuka try to say a fear and goodness of imagination at the same time. That s border of imagination and reality is uncertain is scary. However imagination didn’t necessarily bring him unhappiness and would rather do delight for him.
This animation was unique, and a beautiful picture and good music were very impressive, so I interested in his other works.