Police officers are targeted and killed by an unknown person. Thinking the suspect is connected to the police force, they are keeping quiet about the situation. Though when officer Satou Keiji is injured by this killer, Ran is the only eye wittiness.
Suffering from traumatic shock, she loses her memory of everything in her life. As a result, the killer now knows that Ran has seen his/her face, and plans to get rid of the only eye witness. Conan must find the murderer while protecting his identity.