In the Western Han Dynasty, the world was just beginning to settle down. Under the peaceful appearance, the undercurrent was surging. In the depths of the palace, there were swords and shadows, and murderous intentions were everywhere. A fight for the heir unexpectedly changed the fate of a girl and even the entire Western Han Dynasty. The girl Yun Xi (played by Ruby Lin) escaped from the palace with her wet nurse after a narrow escape from death. She was displaced in her early years and had no chance to love. Fate arranged for her to enter the palace again, but she had to deal with the vicious and suspicious Empress Lü (played by Dai Chunrong) with caution and fear of losing her life. Fortunately, her cleverness made Empress Lü happy, and she secretly sent her to Dai to monitor Liu Heng (played by Chen Jianfeng), the son of Empress Bo Ji, in order to plot a heir. In the turbulent history, the beautiful, passionate, persevering and intelligent Yi Fang was destined to write an extraordinary stroke... This film is based on the novel "Weiyang: Ups and Downs" by Moment Qingcheng.