On the day when Su Yingying (played by Xu Zhenzhen), the daughter of the Su family, the chief assistant of the loyal cabinet, married the second prince Xie Yuheng (played by Zhu Minxin), Xie Yuheng led his troops to kill the whole family on the grounds that the chief assistant of Su was collaborating with the enemy and treason. Xie Yuheng also became the crown prince.position.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 (played by Lin Zehui) and disguised herself as Xie Yi'an's maid Suying.

The two started with the counterfeit banknote case and found that the case was related to Su Shoufu and Xie Yuheng, so they investigated in depth.The two also went from being at odds with each other at the beginning. They worked together and approached the people involved in the counterfeit banknote case regardless of the danger. They got closer to the truth step by step, and thus exposed Xie Yuheng's conspiracy to seek power and usurp the throne. It turned out that Xie Yuheng was notIn order to fight for the royal power, he manufactured counterfeit banknotes to amass wealth, bribed officials and cultivated a killer organization “Suzaku Pavilion” to eradicate dissidents. Because Su Shoufu found out that Xie Yuheng was the mastermind of the counterfeit banknote case before his death, Xie Yuheng ordered his lifeStealing Su's official seal and forging documents indicating that Su was collaborating with the enemy to frame Su.