Boatwoman Liu Yuelian gave her all to support her husband Chen Yuan in going to the capital for the imperial examinations, and right at the time of her childbirth, she risked her life to rescue a drowning infant. Three years later, she took her daughter to the capital to find her husband, only to discover that Chen Yuan had topped the examinations and, in order to marry a princess, lied that she was a distant relative, leaving the mother and daughter to suffer endless humiliation. In the depth of despair, the infant rescued back then transformed into a guardian divine dragon to come and repay the debt of gratitude. As the truth behind Chen Yuan's wealth is uncovered, Liu Yuelian resolves to divorce, and the ungrateful man will also fulfill the riverbank's poisonous oath and suffer heavenly retribution.