A metropolis that is extremely prosperous but has extremely poor public security - Songzhou City. The male protagonist Gao Yun was selected to become a police officer in order to avenge the death of his family. He became an undercover agent and sneaked into the school, determined to search for evidence and avenge his family. Meeting a girl from a similar background, Nao Yingyang, a strong, mature, wise and calm heroine who seems innocent, kind and kind but is unfathomable on the inside, the two gradually change from being defensive to understanding, cooperating, and finally developing a good feeling. During the period when the two parties get to know each other, there are many disturbances interspersed, such as the hero's identity being suspected, the heroine's almost assassination, the self-reliance and perseverance in order to survive, the melancholy and sadness behind the hero's outstanding performance, the contradiction and emotional tension of the two people's mutual attraction and difficulty in falling in love, and using campus, friendship and family as auxiliary lines to make the story more dramatic and dramatic.