Go Mi-nyeo (Park Shin-hye) has lived at an orphanage with her twin brother, Go Mi-nam (also played by Park Shin-hye), since childhood, after their father died. Years later, her brother becomes a music idol, and Mi-nyeo lives in junior nun dorm to reach her dream of becoming a nun. Her idol twin brother Mi-nam, successfully wins the "A.N Entertainment" vocal auditions for musical band "A.N.JELL," but Mi-nam must leave in order to correct his botched plastic surgery in the United States. Ma Hoon-yi (Mi-nam's manager, played by Kim In-kwon) approaches Mi-nyeo to pose as Mi-nam for a month till he recovers. Mi-nyeo is against it at first, but eventually agrees, as a path to fame would give the twins an opportunity to find their mother. Mi-nyeo, posing as Mi-nam, joins the band A.N.JELL and mee