The Detective Boys are at a small ski resort and meet up with four graduate students who are building a snowman for an art project. Later that evening, Sakuko Kokura, one of the graduate students, become lost in the blizzard and the two groups begin their search for her. Conan finds the Kokura dead at the bottom of a cliff in a lake. The police declares that Kokura's death was a snowboarding accident. Conan notices that the body is missing a hat, goggles, and gloves and believes that she was murdered and one of the graduate students is the culprit.
