After returning from a long military campaign, Helian Ye, the King of Mobei, faces fierce disputes at court over the selection of his queen. He chooses Xiao Xuerou, a princess of the Great Sheng Dynasty sent to Mobei in a political marriage, but the tribal nobles vehemently oppose his decision. Wanyan Xiao proposes holding a martial arts competition after the winter hunt, with candidates competing in horseback archery, tea preparation, medicinal herb identification, and other skills to determine the queen. When an investigation reveals that the Old Khatun has been suffering from chronic poisoning, Xiao Xuerou, who is skilled in medicine, uses riding lessons as a cover to treat her with acupuncture and secure a chance to participate in the competition. As the Old Khatun gradually recovers, Xiao Xuerou struggles with her weak horseback archery skills while navigating the treacherous intrigues of the royal harem and preparing for the impending contest to determine the queen.