To repay a life-saving debt, Empress Dowager Jiang Mei takes the place of her deceased daughter, Shen Qingning, and returns to the Marquis's residence, only to be treated as a disposable pawn by the cold-hearted Shen family and sent into the palace. Xiao Xuan, the tyrant feared by all, was actually raised to power by her and obeys only her. When the people in the secret hall recklessly humiliate her, Xiao Xuan kneels before everyone to protect his mistress at the moment of danger. She settles accounts one by one with the ungrateful Marquis's household, the vain imperial consort, and the treasonous Grand Tutor Liu, exposes corrupt officials conspiring in court, and promotes worthy ministers from humble backgrounds. In the end, she governs alongside Xiao Xuan, avenges the old debt for the life-saving grace, brings peace to all under heaven, and safeguards their vast realm together.