During a fictional honest and upright Ming Dynasty, twelve-year-old noble maiden Shen Heng has followed her mother in studying herbal medicine and medical skills since childhood. With a pure disposition, she passionately loves gathering herbs and practicing medicine, while extremely resisting arranged marriages. A pediatric rash outbreak suddenly strikes the capital, with children frequently suffering from itching and pain. Shen Heng's mother brings her to a charitable clinic in the city. Facing the agony of illness directly for the first time, Shen Heng feels timid and nearly retreats, but here she meets Qin Tan, a shrewd, transparent daughter of a medicine merchant well-versed in medicinal ingredients and pharmacology; Zhou Ying, a spirited daughter of a military general with robust martial arts skills; and Nurse Zhao, who is proficient in pediatric tuina and has retired from outside the palace. Displaying their respective strengths, the three of them accompany and encourage Shen Heng.