Orphan Go Mi Nyeo (played by Park Shin Hye) is a nun-in-training with little awareness of what is happening in the world outside her church. Her twin brother, Go Mi Nam, is set to join the hottest band in Korea - A.N.Jell, led by the cool Hwang Tae Kyung (Beethoven Virus' Jang Geun Suk). When an unfortunate accident puts Go Mi Nam out of commission for a month, the band's manager begs Mi Nyeo to take his place - without the knowledge of the other band members. Though unwilling at first, Mi Nyeo realizes this is her chance to find their mother, who disappeared when they were born. As she tries to find her mother, she must also learn how to deal with emotions of love as she grows attached to the lonely Tae Kyung. This drama about an idol boy band and the nun who enchanted them all won the hearts of millions throughout Asia, and brought its leading stars immense popularity overseas.