Lin Qiaoqiao, the second young miss of the Lin family in Jiangnan, is dismissed by everyone as a fool—but in truth she is merely slow to think, needing time to reason her way through matters. Her father, cold and selfish, schemes to climb the ladder of power by forcing her brilliant and beautiful elder sister to marry into the Changning Marquis household alongside her: the sister to the sickly eldest son, and Qiaoqiao herself to the promising second son. Her mother's past tragedy is vivid before her eyes, and each time Qiaoqiao finally sees the world clearly, she strikes out to shatter the trap. As the wedding day draws near, she perceives the calculations behind this match, awakens on the eve of her marriage, and resolves to stop this betrothal that would ruin both sisters' lives.