While playing at the park, Conan, Genta, Mitsuhiko, Ayumi, and Haibara hear a dog barking loudly and a woman screaming. They head to the location of the sound, where they find housewife Yamada Sachiko and her beloved dog Pan being attacked by a man wearing a ski mask. Rather than rescuing his owner, Pan flees during the commotion. With help from Conan and the kids, Sachiko escapes danger. Sachiko, who doesn't know why she was attacked, heads home with Pan once he returns, but Conan and the kids are curious about the masked man's goals and decide to investigate.
