The story is a mystery about a green cat and a private detective who investigates where it came from. The cat was thought to be good luck, but eventually brought misfortune to all those who come in contact. The story was taken directly from the 5th subtitle of the 1950s Lion Books manga.
H!Anime is the best site to watch
The Green Cat SUB online, or you can even watch
The Green Cat DUB in HD quality.
You can also find
Tezuka Productions anime on H!Anime website.