Due to her grandfather's dying instructions, the 10-year-old girl Wei Xi came to Guigu alone with her grandfather's only relic, the Frost Moon Sword. He learned swordsmanship from his grandfather's old friend Gui Guzi. Three years later, as Guiguzi's great apprentice Gai Nie left without saying goodbye, Wei Xi also decided to go out and make a career. Entering the Yin Yang family, was it an accident or a conspiracy? The journey begins...