Shen Zhiyi is the legitimate daughter of the Shen family who was foolish for twelve years. Everyone laughs at her for being an idiot, but she was actually poisoned by the chronic soothing incense of her stepmother Liu. Her mother was killed by this incense fifteen years ago, and her father burned the medical prescription and swallowed her dowry. To fulfill the engagement, she takes her sister's place to marry into the Jing Prince's Mansion, becoming the princess of the cold-faced Prince Xiao Chengjin. The whole capital waits to watch a joke, not knowing that Xiao Chengjin has remembered her for fifteen years, swearing to wait for her to sober up and make her truly fall in love with him. When the poisonous incense is exposed, she becomes sober step by step; during the birthday banquet trouble and the courtroom confrontation, the poisonous woman is executed in autumn, the scum father is dismissed from office and his property confiscated, and the stepsister is exiled a thousand li away. She writes a letter of separation, and he tears it to pieces on the spot.