Osugi Ryota (Kagawa Teruyuki), a former detective of the Tokyo Metropolitan Police Department’s First Investigative Division, resigned from the police because of some incident and now runs a private investigation agency. One day, a beautiful weather girl Koike Risa (Hayami Akari) visits Osugi with a request. She wants him to search for her younger twin sister Rina (Hayami Akari) who was supposed to have died 18 years ago. In the footage of a video that was anonymously put into Risa’s mailbox, Rina is seen to suddenly transform like a beast and attack a counselor in the room of a facility. Risa is convinced that her younger sister is still alive somewhere. And that she is also the criminal who killed her parents one year earlier … … After Risa’s parents were murdered by someone at the research lab of an abandoned university hospital, their hearts were gouged out. Osugi gets his partner, senior patrol officer Narumiya Keisuke (Ito Atsushi), involved. Narumiya starts examining whether anyone is living in Risa’s family home now as well as the scene where her parents were killed. The “ghost of the heart professor” is rumoured to appear at research lab. Narumiya finds something inside the dark, dilapidated place. Meanwhile, Osugi who is going through a divorce settlement with his wife Keiko (Horiuchi Keiko) over the custody of their daughter Megumi (Sugisaki Hana), is asked why he quit being a police officer without consulting his family. But he stubbornly keeps silent. What flashes in his mind are the memories of the case that led to his resignation. The gruesome serial murders by a criminal who is a copycat of Shingai Hiromi, that he pursued together with junior detective Mishima Akifumi (Kiritani Kenta) … …