Starting from the subtleties, even if there are only clues, we can follow the clues to find the real murderer. This is the powerful Criminal Action Analysis Room (CPS). This is a newly established department of the Metropolitan Police Department's Investigation Division. The department includes many outstanding personnel. Among them is Xiangzi Xiangyue (played by Keiko Kitagawa), a new criminal profiler who graduated from the FBI Special Agent Academy in the United States. She is particularly fond of and good at figuring out the psychology of criminals and has a wild imagination; the leader of CPS, Jie Chengjing (played by Kimura Tae), is responsible for the overall planning and control, and is the absolute core of the team; Keisuke Shinbori (played by Yuta Hiraoka), who has 2 doctoral degrees, uses statistical analysis methods to find the hiding place of the suspect and regards Xiangzi as a competitor. In addition, this team also includes forensic doctors, IT, section chiefs and others. A strong team makes the seemingly perfect crime without leaving any traces full of loopholes. It is not the traditional method of investigating cases that only stays on the surface, but to dig out the reasons behind the crime. The criminal psychology analysts bring a wonderful investigation process.