In the ancient fictional dynasty "Da Ning Dynasty", after the Li family of the Marquis of Kyoto became the founding father of the country, they were granted the title of "Dingbei Marquis" for their military exploits and guarded the north for generations. The heroine Li Zhaoning is the legitimate daughter of the Marquis of Dingbei. Her mother Su is the daughter of a minister. She died early due to frail health after childbirth. Her father Li Hou remarries Wang as his stepmother. Wang brings her concubine Li Zhaoxue into the house. From then on, Li Zhaoning is ignored and bullied. She appears to be weak and can be bullied, but in fact she hides her edge. She uses her weakness as a cover to secretly collect evidence that her stepmother embezzles family property and poisons her mother. As Shen Yanzhi, a member of the Jin Yiwei family, intervenes in the Hou Mansion to investigate the case, the two go from testing each other to jointly uncovering the collusion conspiracy between the Hou Mansion and the remnants of the previous dynasty. Li Zhaoning counterattacks his opponents step by step and regains control of the Hou Mansion. At the same time, he and Shen Yanzhi break through identity barriers to achieve family rejuvenation and personal happiness.
