While out on a trip for their homework assignment, Conan and the Junior Detective league rescue a young girl being assaulted. She later comes to the detective agency to speak with Kogorou. They decide to investigate after learning that a treasure is ... (more)involved. During their travel to Tsuwano, the young girl meets with her friend, who seems suspicious. While investigating, the girl, Haibara, and Mitsuhiko are abducted.