Zhong Taiyan (played by Ma Guoming) studied clinical psychotherapy and became a psychoanalyst after graduation. He knows the darkness and complexity of human nature. Zeng Xiuyi (played by Tong Luwen) is Zhong Taiyan's girlfriend and also a psychoanalyst. In a brutal and terrible homicide case, the murderer Lu Jianqiang (played by Wei Jiaxiong) was brought to justice and sentenced to life imprisonment. However, the matter did not come to an end. The father of the victim in the case actually drove a car to kill Zeng Xiuyi, just because Zeng Xiuyi issued a report stating that Lu Jianqiang's mental state and personality were very simple and did not look like a murderer. The news of his girlfriend's death plunged Zhong Taiyan into despair and grief. He saw Lu Jianqiang's psychological report and found that everything his girlfriend said was true. This means that from a psychological point of view, Lu Jianqiang could not have committed the crime, and the real murderer was someone else.