Songyin, a genius poison doctor, dies with intense resentment after sacrificing her life to shield the novel's heroine, Jiang Tan'er, from an assassination attempt. Upon her death, she discovers she is merely a supporting character in a fictional work titled The Prince's Unending Flirtation. The narrative reveals that Jiang Tan'er, a transmigrator from another world, had concealed Songyin's true identity as a lost daughter of the prestigious Xie family, ultimately leading to the destruction of Songyin's blood relatives under the guise of protection. As Songyin lies dying, a system activates, initiating a World Evolution process that rewinds time to her childhood, granting her a second chance to alter her fate within a five-year window.
Songyin awakens in her younger body, moments after being slashed by Xie Jiyan, the twelve-year-old son of the Xie family. In the original timeline, this injury delayed her treatment of the Old Imperial Uncle, causing severe repercussions for the Xie family. Recognizing the opportunity to break free from her predetermined role as a tool character, Songyin confronts the boy and asserts her dominance. When Jiang Tan'er arrives, feigning concern, Songyin publicly slaps her and exposes the manipulation behind the incident involving Xie Jiyan's sister. She reveals that Jiang Tan'er used a medicinal drug to humiliate the Xie family, shattering the facade of their close friendship.
Refusing to be further controlled, Songyin severs ties with Jiang Tan'er and makes a bold move by traveling to the Xie residence. She claims to be the long-lost biological daughter of the Marquis Xie, a woman who died during a famine years prior. Although the Xie family is skeptical and hostile, Songyin leverages the political pressure from the Old Imperial Uncle to force their hand. By declaring the sword attack a familial dispute, she prevents Xie Jiyan from receiving severe punishment and secures her place within the Xie household. The family, particularly the elder brother Xie Jiling, agrees to let her stay temporarily to investigate her true origins while maintaining the appearance of reconciliation.
Once inside the Xie estate, Songyin begins to dismantle the advantages Jiang Tan'er had previously monopolized. She identifies Qu Zhongjie, a commoner who had unknowingly credited Jiang Tan'er for saving his grandmother's life, and forcibly recruits him along with his grandmother. Songyin reclaims the peanut seeds Qu Zhongjie had intended to gift to the heroine, recognizing their future economic value. She plans to cultivate these crops independently and use the resulting wealth and imperial favor to strengthen the Xie family's position, thereby creating a power base independent of Jiang Tan'er. The story follows Songyin's strategic efforts to rewrite her destiny, expose the transmigrator's anomalies, and ensure the survival and prosperity of her biological family, all while navigating the fragile political landscape of the capital.
