Set in the Joseon Dynasty, at that time, twins were considered an omninous sign for the royals. As a result, when the crown princess gives birth to twins, an order is sent to kill the daughter among twins. To save that daugther's life, crown princess secretly sends someone and moves her out of the palace. A few years later, the twin daughter Da Mi returns to the palace to work as a maid. When the male twin, Lee Hwi, loses his life through a case of mistaken identity. Their mother persuades Da mi to take Lee Hwi's place. From then, she distances herself from everybody while living in the lonely palace and hiding her secret. However, Lee Hwi starts developing feelings for Jung Ji Woon, her original first love and later teacher who comes from a noble family. However, as she needs to live her life as a king, Lee Hwi, she cannot confess her feeling to Ji Woon.