Yang Yuan, a modern woman, transmigrates into the body of a sixteen-year-old girl in 1970s China, finding herself in the world of a period novel she once read. In this harsh era, she inhabits the role of a minor antagonist: the fake best friend of the novel's heroine, Song Can. The original Yang Yuan was jealous and malicious, burning a love letter from Song Can's first love and meeting a gruesome end after murdering her unfaithful husband. Determined to avoid this fate, Yang Yuan decides to stay out of the main plot and secure her own survival. However, her plans are immediately threatened when she learns that she, like many other youths, is scheduled to be sent to the countryside. Refusing to leave the city, she identifies Song Can as her only viable path to safety, since Song Can has just secured a coveted office job at a state-owned textile dyeing factory.
Yang Yuan approaches Song Can with a pragmatic proposal: she will buy the job from her. While Song Can is being blackmailed by her stepmother into giving the position to her stepsister, she agrees to sell it to Yang Yuan instead, viewing it as a way to deny her family the benefit. Yang Yuan needs to raise seven hundred yuan, a staggering sum in an economy where a monthly wage might be less than fifty yuan. To acquire the necessary funds quickly, she devises a scheme based on a scene from the novel. She learns that her fourth brother, Yang Wenping, is engaged to Zheng Yuyin, a girl from a wealthy family. Yang Yuan stalks Zheng Yuyin and discovers her meeting with another man in an abandoned house, revealing that Zheng Yuyin is pregnant with another man's child. Yang Yuan ambushes the couple, threatening to expose them to the authorities for hooliganism unless they hand over their money. She successfully extorts five hundred yuan from Zheng Yuyin, justifying the theft as retribution for the betrayal of her brother.
Upon returning home, Yang Yuan is discovered by her parents, who are furious about her absence and her strange attire. During a heated confrontation, she reveals the secret she uncovered about Zheng Yuyin. The revelation shocks the family and halts the wedding preparations. Yang Yuan uses the extorted money and funds borrowed from relatives to pay Song Can. The transfer of the factory job is completed, and Yang Yuan secures her position as a white-collar worker, effectively removing herself from the list of youths destined for the countryside. She also apologizes to Song Can for the original owner's past betrayal regarding the love letter, establishing a new, transactional boundary between them.
With her job secured, Yang Yuan focuses on integrating into this era and living a quiet life. Meanwhile, the fallout from her discovery of Zheng Yuyin's infidelity causes significant turmoil. Yang Yuan accompanies her mother to the Zheng residence to confront the family about the broken engagement and the return of the bride price. The confrontation is tense, with the Zheng family attempting to shame the Yangs, but Yang Yuan stands firm, defending her family's honor. The story concludes with Yang Yuan having successfully altered her destiny, trading her role as a background villain for that of a working woman, while navigating the complex social and familial dynamics of 1970s China.
