The film capturing the changing environment of Tokyo with Olympic games through an old man lives with abandoned cats wile catching clams in the tideland of the Tama River. This is a documentary film with reflecting the flow of the times from Showa to Heisei and Reiwa era on his life From the “downstream” of the city, Various issues facing Japan today will be highlighted such as environmental destruction, aging society, poverty, economic disparity, abandonment of pets, and biodiversity and so on.
