Zhang Wanqing's husband, Li Guoan, dies in a coal mine accident. Her mother-in-law, upset that her second child is a girl, throws Zhang Wanqing and her older daughter out and sells the newborn. Desperate, Zhang Wanqing leaves a bite mark on the baby's arm as an identifying sign. The infant is rescued and adopted by Tang Qingshan, who has secretly loved Zhang Wanqing for years, and names her Tang Xueli. Years later, Zhang Wanqing accidentally travels back to age eighteen and becomes a maid in the Tang household, where she is misunderstood and humiliated by Tang Xueli. After an accidental fall down the stairs, Zhang Wanqing sees the bite mark on Tang Xueli's arm—and realizes she is her long-lost daughter.
