Ye Feng, the successor of Xuanhu Pavilion, obeys his master's order to descend the mountain to fulfill an agreement. On a rainy night, he encounters Leng Ningshuang, the eldest miss of the Leng family, in danger, and chivalrously steps in to help. The two form a bond over a yellowed marriage contract. Relying on his superb medical skills to treat the injured, and with wisdom and responsibility to resolve wave after wave of crises, he protects Leng Ningshuang and the Leng family through difficulties, and also uncovers a dusty twenty-year-old past between the two families and an unknown mystery of his birth background.