Detective Shimura Takafumi belongs to the Special Investigation Unit which investigates unsolved cases that happen within the Tokyo Metropolitan Police Department’s jurisdiction. He used to be in charge of investigating cases on the First Investigation Division’s front line. However, his zeal for arresting criminals was particularly strong among the detectives of the division and the extremes he would go to in investigations led to his demotion. He is considered dangerous by the people around him in certain situations and his sense of justice is close to an obsessiveness. Shimura ends up having to work with Kiriko, a crime coordinator who is the representative of “evil” so to speak. Called “Invisible” because she is known only to a group of people within the police organisation and no one has seen her real image, Kiriko dominates the underworld and brokers deals for violent criminals. One day, she suddenly offers to help the police arrest criminals. Her only condition is that she wants to work with Shimura. She is privy to information on criminals that the police has yet to grasp and seems to hold the key to solving a lot of the unsolved cases that Shimura is pursuing. What is her motive for getting close to him?