In the newly formed Shiniki district of Tokyo, Zen Seizaki serves as a diligent public prosecutor at the Tokyo District Public Prosecutors Office. Assigned to a case involving false advertising, Zen—along with his assistant officer, Atsuhiko Fumio—investigates Japan Supiri, a pharmaceutical company that had provided fabricated clinical research on its new drug. While reviewing the file of Shin Inaba, an anesthesiologist connected to the crime, the case takes a dark turn when Zen discovers a page stained with a mixture of blood, hair, and skin, along with the letter "F" scribbled all across the sheet. As he investigates further, the case goes beyond Zen's imagination and becomes vastly complex, challenging his sense of justice and his knowledge of the truth. Digging deeper into the investigation, Zen begins to uncover a concealed plot behind the ongoing mayoral election and ties to many people of interest involved in the election and those closer than he thinks. The case grows more severe and propels Zen into an unforeseen hurricane of corruption and deceit behind the election, the establishment of the Shiniki district, and the mysterious woman associated with it all.