While on their way home from visiting Professor Agasa's friend's apartment, Conan, Ayumi, Mitsuhiko, and Genta hear a scream. They rush to the scene, where they discover a man bleeding from the head as well as a woman. The woman who lives at the apartment noticed something off about the place when she came home and grabbed the golf club she kept for self-defense. The lights wouldn't turn on, and as she entered the apartment, she heard a loud noise... The police confirm her story and believe it was an unfortunate accident. However, certain elements of the case catch Conan's attention...