Crown Prince Xiao Dingquan lost his mother and sister when he was young and was not close to his father. His early experiences made him extremely eager for family affection, and he always tried his best to keep the only relatives around him. Xiao Dingquan respected and feared his father. He hoped to gain his father's affirmation, but was afraid of the dilemma when his hopes were dashed. The King of Qi and his father-in-law, the Secretary of State Li Baizhou, repeatedly created troubles, not only persecuting the only people Xiao Dingquan cherished around him, but also deepening the gap between Xiao Dingquan and his father. The prince's teacher Lu Shiyu once hoped that the clear stream Lu Ying would succeed him as the prince's solid backing. Unexpectedly, Lu Ying's daughter Lu Wenxi met the prince by chance and got to know him, and then secretly promised to be together for life. After the people close to him were killed one after another, Xiao Dingquan, who was deeply influenced by Lu Shiyu's Confucianism, firmly fought against the villain's conspiracy with the gentleman's code of family, country and the world. After her father and brother met with disaster, Lu Wenxi transformed herself into a female official of the East Palace and silently guarded Xiao Dingquan. She helped him solve the military horse case and the nursery rhyme case, and finally cleared the grievances of her father and brother and brought the treacherous villain to justice. Xiao Dingquan and Lu Wenxi also deepened their feelings as they cooperated with each other. The two timid but brave people were not afraid of hardships and sacrifices, and they stayed together for the peace of the country.