S1, E4: In a chaotic world with three split kingdoms, a doctor Han Yun Xi marries into a royal family.Being a kind-hearted woman from a medical family that excels at potions, she struggles with following the word of the king and convinced by the Empress Dowager of Tianning to become a spy in exchange for information on her mother who disappeared years ago.How will Yun Xi's story in the palace unfold.