With the help of Conan's detective skills, the identity of the culprit who murdered MPD Transportation Department officers Momosaki Toko and Yagi Shiori is determined. Additionally, the police learn that one week earlier, the culprit heard the name "Yumi" while he was being disciplined for a traffic violation. Though the name referred to someone else, based on the victims' mutual acquaintances, it's possible that Transporation Department officer Miyamoto Yumi may be his next target, and the search for the culprit begins. However, no one can get in touch with Yumi...