Penghai City Public Security Bureau detected that the city is hiding two drug lords "Playboy" and Wu Hongkai. In order to eliminate them, director Chen Wentao set up a task force responsible to solve the case. The police officer Gao Zhiyuan is grief-stricken by the unexpected death of his fiancée. Chen asked Gao Zhiyuan to secretly join the task force and asked him to go undercover to collect evidence for Wu Hongkai's company on the pretext of avenging his fiancée, Ai Li. With his natural vigilance and extraordinary qualities, Gao Zhiyuan, under the leadership of Director Chen and with the cooperation of all the police officers in the city bureau, overcame many difficulties to find out the truth and solve the mystery, and justice prevailed over evil. Gao Zhiyuan completed the difficult task assigned to him by the organization, and also brought light to his fiancée Ai Li who was killed innocently....