A professor of Asian Studies at a small Midwest university unexpectantly receives an ornately carved ivory box that contains five scrolls dating to 13th Century China. The scrolls describe the life of a young Chinese Apprentice Physician, who at the age of fourteen is responsible for saving a dynasty and the world's largest city from destruction His father is the personal physician to the Emperor of the Jin Dynasty. The time of the story is during the Mongol invasion of China.