A top-tier secret agent's soul transmigrates into Hua Jinyue, the bullied foolish daughter of a marquis's estate, carrying a magical storage space with her and possessing modern knowledge. On the night of the palace coup, she stumbles upon the secret of the National Preceptor Shen Yuyuan committing murder. Holding leverage over each other, the two are forced into an entangled relationship. She sets up a stall to do business and strives to support her family, protects her older brother, helps bullied and vulnerable people, and smartly talks back to villains to resolve troubles. The crazy-genius National Preceptor is emotionally stirred by her lively and unfettered nature. The two pull and tug in a game of wits, navigating together through the perilous political chaos of the imperial princes' struggle for the succession.