A love story about Princess Nak-rang who fell in love with a spy from Goguryeo. She tore the drums of her country so that Goguryeo could attack her country, Nangnang-guk, without warning. However, Nak-rang's love story with Hodong is further complicated due to the fact that Nak-rang's older sister Ja Myung is in love with Hodong as well.

The story focuses on the conflicts between the young teachers and the problems that high school students have. Jang Yi San is a timid and incompetent classical music teacher who has to teach the only daughter of a highly dangerous mob leader. Eun Byul is the mob leader's daughter and she is also a new student at MyungMoon High but knows nothing whatsoever.