Shen Zhaoning, the legitimate daughter of the Marquis of Zhenbei's household, has long been bullied by her stepmother, Madam Zhou, and her stepsister, Shen Yurou. Her mother died young, and her father is consumed by military affairs. Clever and patient, Shen Zhaoning secretly gathers evidence that Madam Zhou has embezzled family assets, plotted against the legitimate heirs, and schemed to marry her off to a wealthy merchant. She first exposes the flaws in Madam Zhou's management of the household and reclaims control of it, then foils Shen Yurou's plot to steal her marriage and wins the right to choose her own spouse. When a crisis involving enemy spies later threatens the marquis's household, she helps her father resolve it and earns his trust. Meanwhile, her relationship with Gu Huaizhi, a hostage prince from the enemy kingdom who is residing in the marquis's household, grows from mutual exploitation into love. After Gu Huaizhi's identity is exposed, the two face the enemy's threat together. In the end, Shen Zhaoning becomes the true power behind the marquis's household and defeats Madam Zhou's clan, while Gu Huaizhi carries out his revenge plan. Together, they protect the household and the nation.
