The late 19TH century, Li NanSen is the daughter of the San Francisco Chinese leader Mei Xilin. As a child, she is separated with her father, who is involved in building of railways. She makes friends with Ah Hee who eventually repatriates to China. Fifteen years later, Li NanSen is a well-known doctor of Chinese medicine in Chinatown who has been disguised as a man to practice medicine. A Nan reacquaints with Ah Hee, but Ah Hee already has another love.
Cary plays Charles, the private doctor for a wealthy American businesswoman Lin Mai. At first he clashes with Lin NanSen over her Chinese medicine practices, but eventually understands the power of herbal medicine. He subsequently falls in love with her and fights for her and in the end, her life.