The Crown Prince of Yan, Yu Feichen, is marrying Yin Nanyao, the daughter of the general who guards the country. The bride is a replacement assassin who comes to claim her life. As soon as she enters the mansion, she encounters the Crown Prince who suddenly dies and wants to be buried with him. The assassin Yue Jian hurriedly contacts the Second Prince, who is an insider in the organization, but she does not know that the Crown Prince is actually playing two roles to lure the law enforcement. Yue Jian maneuvers between the Crown Prince's Mansion and the organization, and becomes more and more reluctant to attack Yu Feichen. Yu Feichen has a panoramic view of the overall situation with two identities, and is increasingly reluctant to expose Yue Jian...