Conan, Ayumi, Mitsuhiko, Genta, Haibara, homeroom teacher Sumiko Kobayashi, and assistant homeroom teacher Rumi Wakasa meet Amuro on the bus heading to Hatoyama Farm. Also on the bus were Junya Hizuka, Takashi Minami, and Shogo Kano, who seemed to have some purpose in mind. While Conan and his friends are spending time at the ranch, Kaisuke Hatoyama, who claims to be the rancher's brother, appears before them. Kaisuke takes Ayumi hostage, and Conan, Amuro, Mitsuhiko, and Kobayashi are locked in the basement of the office. There they find the body of the rancher, Gisuke Hatoyama, and Yuya Kazami. Conan succeeds in contacting Haibara and the others who remained above ground, but then the three passengers on the bus and Kaisuke arrive. What is their intention?