Kana Kurosaki was appointed to be in charge of investigating Serial Strong ● Murder ● Criminal X. However, information about X is scarce, and his identity is unknown, let alone his name, and there is not even a decent photo of his face. Kana's father, Goro, who was once a special agent, was also instrumental in investigating X, but he was martyred in the middle of his aspirations. Kana visits Eiji Kagami, a former subordinate of her father and the man closest to X, and asks for his cooperation in the investigation. However, this Eiji Kagami is X. Kagami takes an interest in Kana and uses a drug to take her unconscious and...