Set during the Republic of China, when each region of China was ruled by local warlords. The Dou family of Foshan is an affluent family that owns and runs Sheung Chun Tong (尚春堂), the largest traditional Chinese apothecary in town. Bad times, however, came during an epidemic. When the apothecary's product caused the death of the Mayor's eldest son (and owner Dou Sam's soon-to-be son in law), Dou Sam is imprisoned, and the apothecary was ordered closed. Sam's only daughter, Dou Gaai Kei, then took on the task of investigating her fiance's death, in hopes of releasing her father. Together with Ding Yat Yuen, a businessman of dubious reputation, they stumble upon a big conspiracy that could rock Chinese politics.