Hajime Kindaichi attends a high school with seven rumoured mysteries, where it is believed that anyone who knows about them will be cursed, leading Kindaichi to try and uncover the source of the mysteries.
Kenmochi, Kindaichi, Miyuki, and Saki go on a fishing tour to Seiren Island where an eerie sound emanates. The sound is said to be the cry of a siren, a sea creature that draws people into the sea with its voice and devours them.
Kindaichi and Miyuki are on a family trip to Hakuja Village. Where they learn that the village has a tradition of worshipping white snakes as messengers of the gods.
Kindaichi is charged with assaulting police officers and stealing their service weapons. Kindaichi's quest to find the real killer grows when he learns about Miyuki's concern for him.
Kenmochi enlists Kindaichi and Miyuki's help when a threatening letter arrives at the home of the inspector's childhood friend, Shino Tatsumi, who married into the prestigious Tatsumi family.
