This drama is a romantic love story about a man and a woman from different backgrounds. Lee Young is the Crown Prince of Joseon Dynasty who likes to break away from his routine life in the palace. Hong Ra On comes from a very poor family that she has to disguise herself as a man to make a living. One day, the moneylenders sell Ra On to the Office of Eunuch Attendants to get back their money. Ra On and Young keep running into each other as she starts to work as a eunuch.
Park Bo-Gum as Prince Lee Yeong
Kim You-Jung as Ra On (Hong Sam Nom)
Jin Young as as Kim Yun Seong
Chae Soo-Bin as Jo Ha Yeon
Kwak Dong-Yeon as Kim Byeong Yeon