The Detective Boys along with Kogoro, Ran, and Sonoko take a trip to Kumamoto, Kumamoto so the Detective Boys may participate in a Tennis Tournament. Ran and Sonoko explore the city and finds a cell phone on the floor. When Sonoko picks up the phone, an unknown person sends her a message declaring their love for her and leaves a location and time so they may meet. Ran and Sonoko allocate to the meeting place. While Sonoko is in the bathroom, Ran overhears three men planning to murder someone. To hide their conversation, the men kidnap Ran. Ran awakens in a locker room with her hands tied and using the phone, manages to contact Conan. She tells him her current situation and describes her surroundings. The three men return and destroys the phone Ran was using. The Detective Boys along with Kogoro and Sonoko report the kidnapping to the authorities while Conan wonders what the objective of the three men is.