Lan Xiaoyu, a plain-looking lady from Beijing, is always forced by her father, a magistrate, to go on blind dates, but she already has someone in her heart - she has always had a crush on the most handsome man in Beijing, Prince Wei Qing. An accident caused her to exchange souls with Chi Jingyu, the top assassin of the Qingluan Society. Lan Xiaoyu became a peerless martial arts master and secretly infiltrated the Qingluan Society to investigate an assassination case on behalf of Chi Jingyu...