This short film takes place in a distant country where imagination is a sin.
The main characters in this film are the boy and the fish which transforms into a fish.
Since the country the boy lives in prohibits imagination, he gets arrested for imagining and they make him unable to imagine.
The climax is the part where the fish turns into a mermaid and astonishes everyone.
I think that Osamu Tezuka wanted to tell us that imagination can make our life more wonderful and happy and without imagination, life may be boring.
