Black Widow Business

Kozo Nakase participates in gatherings for widowed individuals seeking new partners. During these meetings, he encounters Sayoko Takeuchi, and they soon wed. Shortly after their marriage, Kozo unexpectedly collapses and passes away. He bequeaths all his possessions to Sayoko, excluding the rest of his family from his will, including his daughter Tomomi. In response, Tomomi enlists the help of a private detective named Honda to uncover more information about Sayoko.