In the newly formed Shiniki district of Tokyo, Zen Seizaki is a diligent public prosecutor at the Tokyo District Public Prosecutors Office. Assigned to a case involving false advertisement, Zen—along with his assistant officer, Atsuhiko Fumio—investigate Japan Supiri, a pharmaceutical company that had provided fabricated clinical research on the companys new drug. While investigating the file of Shin Inaba, an anesthesiologist connected to the crime, the case takes a dark turn when Zen finds 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 Zens imagination and becomes vastly complex, challenging his sense of justice and his knowledge of the truth.