In the first year of Tianqi, Emperor Tian Qi sent two imperial doctors, Li and Song, to search for the elixir of life recorded in the lost volume of Huangdi Neijing. The two families had a deep hatred because of a misunderstanding of stealing medicine. After years of searching, they finally got the elixir of life, but when they opened it, they found that it was actually two pills: one was a deadly poison, and the other was an elixir of life. Emperor Tian Qi took the poison by mistake and died. The court then slaughtered the entire family of Li and Song. Fifteen years later, Li Shi, the only survivor of the Li family, and his third uncle opened an inconspicuous clinic in the city to make a living. At the same time, Song Gai and Song Ling Fei, the surviving siblings of the Song family, returned to Tianqi City to seek revenge on Li. In order to protect the clinic and his third uncle, Li Shi had to go to war with him. But Song Gai's appearance did not seem to be just for revenge. Behind it seemed to be a secret about the death of Emperor Tianqi. All the clues seemed to point to the night when the emperor died fifteen years ago...