"Mysteries of the Tang Dynasty" is a suspenseful detective work with two male protagonists set in Chang'an of the Tang Dynasty. It tells the story of Su Lian, who is thoughtful and good at reasoning, and his partner Li Dangdao, who is upright, brave and very capable. Starting from solving the Liu Mingyuan case, they successively uncovered a series of mysteries such as the undercurrent of the East Palace, the secret language in the painting, and the Mingjiao rebellion. Amidst the dazzling swords and the treacherousness of the court, the story of upholding justice and guarding the tranquility of Chang'an.