A female college student falls from a building in an unexpected way. Cheng Rui (played by Zhou Yiwei), the newly transferred deputy captain of the Criminal Investigation Detachment, is assigned by Deputy Director Du Yulin (played by Wang Jinsong) to investigate the hidden story behind the incident. He finds that the case is related to gangster crimes such as routine loans and violent debt collection. An Yiming (played by Zeng Zhiwei), an entrepreneur in the city, is listed as a key target of investigation. Cheng Rui wants to investigate further but is asked to close the case as soon as possible. Who is acting as a "protective umbrella"? The city is in crisis. An Yiming's wife Zhou Tong (played by Qin Hailu) and economics professor Zhao Xianyu (played by Zhang Zhilin) are caught in it. In order to restore peace to the people, Cheng Rui and his colleagues break through difficulties and track it down to the end, but they don't expect that there is a bigger conspiracy behind it. What is the truth? Can they wipe out the evil hidden in the darkness?