Su Yingying, the daughter of Su, the chief assistant of the loyal cabinet, married the second prince Xie Yuheng, Xie Yuheng led his troops to kill the whole family on the grounds that Su's chief assistant had collaborated with the enemy and treason. Xie Yuheng also ascended to the position of crown prince. Three years later, Su Yingying returned with the intention of redressing her father's injustice and investigating the case of collaborating with the enemy and treason. She joined forces with the seventh prince Xie Yi'an and disguised herself as Su Ying, the maid beside Xie Yi'an.