The Detective Boys are in a puppeteer camping trip, where they are practicing for a school puppet play. At the same time, a serial killer has been spotted near the areas of the camp. While at the camp, the students disappear with their puppets, leaving the Detective boys alone. Mitsuhiko assumes that their teacher is the serial killer. After they disspear, only Mitsuhiko remains alone. After being cornered by the teacher, Mitsuhiko finds out they decided to scare him for being bossy, by the suggestions of Genta and Ayumi. Mitsuhiko runs away angrily but runs into the serial killer. Conan manages to stop the serial killer and he is arrested. Later, Ayumi kisses Mitsuhiko for playing that mean joke on him.