Main characters on this video was a boy, a fish/mermaid, and the government. I'm not really sure when and where this happened, but I think it may be the time during World War 2, because the boy didn't have any freedom to imagine. For the boy, a fish looked like a mermaid, but for others, it was just a normal fish. He wanted everyone to understand what he is seeing, but at that time, no one had freedom to say something different from everyone else, so he was punished.
I couldn't tell which part was real and which is fantasy, but I think everything was real except for the existence of the mermaid. However, in the end, the boy and the mermaid was swimming together. I believe that the boy also turned into a mermaid because he believed that the mermaid exists.
I think what Tezuka Osamu wanted to tell us was "Don't always think what you believe is correct. There are other perspectives than your's, so listen to what others say."
