Ningyo
English title: Mermaid
Japanese title: 人魚
Type: Movie
Source: Original
Episodes: 1
Status: Finished Airing
Aired: Sep 21, 1964
Duration: 8 min
Rating: G - All Ages
Studios: Mushi Production
Genres: Fantasy

In a fictional place where using the imagination is banned, a boy saves a fish, which surprises everyone by turning into a mermaid. The boy is arrested for imagining this "nonsense", and is robbed of his imagination as punishment. 

(Source: ANN)