During the Wanli period of the Dajing Dynasty, Li Xiuyuan, the imperial physician of the imperial hospital, had superb medical skills and adhered to the benevolence of doctors. In order to compete for favor, the concubines in the harem repeatedly asked him to prescribe harmful medicines, but he refused. Therefore, he was suppressed by the concubines. Once, the emperor suddenly became seriously ill and the cause was unknown. Li Xiuyuan made a careful diagnosis regardless of his own safety and found that the cause was man-made poisoning. He developed an antidote to revive the emperor, uncovered the poisoner, and exposed the harem's conspiracy. Although he offended the powerful, he won the emperor's trust.