The third work of the popular series depicting the famous detective Kyosuke Kozu. Blind musician Ryoichi Kashiwagi died of a heart attack. His father, Shigeyuki , is already bedridden and has billions of Japanese yen in assets. Ryoichi's wife Yukiyo and Ryoichi's younger sister Tsuruko have a dispute over these assets. Newspaper reporter Matsushita, who met Ryoichi just before his death, was interviewed, and was told that there was something unnatural about Ryoichi's cause of death. Soon, Tsuruko died mysteriously. Matsushita decides to have Kyosuke Kozu, a university professor and a famous detective, solve the case.