The medical girl Yun Qingci was responsible for the unjust case of extermination of her family. She was proficient in medical and poisonous skills and lived in seclusion in the seventh prince's mansion. The seventh prince, Lu Jinheng, was poisoned by a secret poison and pretended to be weak and dormant to avoid disaster. Amid the numerous crises set up by the powerful minister Pei Hongyuan, assassinations by the Blood Shadow Cult, turmoil in the court, and traitors in the palace, the two have a tacit understanding of each other and protect each other. They work together to uncover the poisonous schemes, investigate old cases, and finally uncover the traitors, clear the grievances, and maintain peace in the court.
