In a story in Poland, two young people who grew up together disregarded the advice of a mysterious traveler and betrothed their unborn children to them, not sacrificing their lives for future generations. Shortly thereafter, one of them died and the other's wife died in difficult childbirth. The children grew up in different towns and never knew about engagement, but the power of vows allowed them to meet at the appropriate time of marriage. The young woman Leah was promised to marry another man, but the son of the deceased father, Qian Nong, was a practitioner of mysticism and attempted to win his bride through magic.