The story mainly tells about the young death of the prince of Duke Dingguo. In order to stabilize the military power and ensure that the Han family army in the north is not affected by the court, the eldest daughter of Duke Dingguo, Han Yuanniang, replaced her twin brother Han Shiyi as the prince of Duke Dingguo. Han Shiyi portrayed himself as a playboy who was romantic, lustful, and unlearned, but unexpectedly became the companion of the fifth prince Chen Yanyi. After being "forced to stand on the side" of the fifth prince, he helped the fifth prince to make plans to seize the position of crown prince. In this series of storms, the fifth prince and Wang Zhongyu, the son of Prime Minister Wang, discovered Han Shiyi's identity as a woman and secretly fell in love with her. During this period, a series of ridiculous stories happened.