The suspense story begins when Jin Saeki, a policeman in Yamanashi Prefecture, arrives at a prominent estate residence in response to a tip, and finds the skeletal remains of 13 children, as well as a mysterious marking. Jūzō Haikawa, the long-missing owner of the estate, immediately becomes the prime suspect. Saeki collaborates with a woman named Kanon Hasumi, who has a connection to Haikawa, and together they search for the truth behind the case. In a parallel story set in Tokyo seven years after the case, a girl with a connection to the mark left on the Haikawa estate runs away from home.