The Hokkaido Serial Murder Case: The Okhotsk Disappearance is a graphic adventure game set around a grim chain of serial murders stretching from Tokyo to the northern landscapes of Hokkaido. The story begins when a man in his forties is discovered floating in Tokyo Bay, but the case quickly expands as further murders connect the capital to cities and regions such as Kushiro, Abashiri, Shiretoko, and Monbetsu. A mysterious Nipopo doll and its tears add an eerie note to the investigation as the truth slowly unfolds.