Kogoro, Ran, and Conan are walking when they witness a car attempting to kill a girl and her chauffeur. After saving the two, they learn that the girl, Kaede Nakakita, is an adopted child of a wealthy man named Ouzaburou Katayose. Katayose invites the three to his estate to express his gratitude towards them. As Conan explores the estate with Nakakita, he finds evidence that someone wants to kill her and deduces the culprit is either Katayose's son, Ogito Katayose, or his daughter, Nobue Katayose who are after the inheritance. Later, Katayose is found dead after consuming poison in his tea. The chauffeur Eiko Suzuka, then reveals Katayose's will detailing the location of his red leaf treasure.
