Detective Kyosuke Kozu's Murder Reasoning 7 (1987)

The 7th popular suspense series based on the original work by Akimitsu Takagi. Along with Kogoro Akechi of Ranpo Edogawa and Kosuke Kindaichi of Seishi Yokomizo, Masaomi Kondo will play Kyosuke Kamizu, one of "Japan's Three Greatest Detectives", and will solve numerous challenges! A threatening letter foretelling the murder of the entire family came to the house of Tobe, who presides over the infamous investment group. Kumiko Toki, the third daughter of the family, consulted with the police, but she simply thought it is done by someone who recently lost investments. Kenzo, a reportage writer who was listening, became interested and brought the threatening letter to Kozu, asking him to investigate...

Unfortunately the movie Detective Kyosuke Kozu's Murder Reasoning 7 is not yet available on HBO Max.