Hyeseo and Sunil have been friends since childhood. Through a past-life regression experience, they discover that in a previous life, Hyeseo was the lady of the house and Sunil was her servant, Dolsae. Despite the forbidden nature of their bond, the two shared a passionate relationship in that life. The heated atmosphere between the mistress and her servant lingers, stirring subtle feelings in the two even after they awaken from the experience. In the end, they become physically involved in real life as well, and their childhood friendship changes in a big way…