In this drama, South Korea has transformed into a constitutional monarchy. Recently, as the emperor's health deteriorates, the high school crown prince Lee Shin (played by Ju Ji-hoon) promises the empress dowager that he will marry the girl with whom he had previously arranged a marriage, in order to fulfill his father's wishes. In fact, Lee Shin had secretly been in contact with the girl, Hyolyn, for some time without telling anyone, and when he proposed to Hyolyn, she flatly rejected him. Although Lee Shin was heartbroken over losing his beloved, he felt a slight comfort knowing that Hyolyn would not have to become a puppet in the palace, losing herself and being controlled by others. The girl to whom Lee Shin was betrothed is high school student Chae Kyung (played by Yoon Eun-hye), who comes from an ordinary family in Korea. She is neither extraordinarily wealthy nor of noble background, and even her grandfather often mentioned that Chae Kyung was engaged to the crown prince, leading everyone to think he was just fantasizing. It wasn't until Chae Kyung's family received a letter from the royal family that they realized her grandfather was not just boasting! Just as Chae Kyung's family rejoiced, the unconventional Chae Kyung announced that she would refuse this arranged marriage, but the family's predicament ultimately forced her to accept it. At this moment, the son of the late Crown Prince Hyol Yeol, who died in a car accident 14 years ago, Lee Ryul (played by Kim Jung-hoon), returns to the palace to claim the throne. What kind of upheaval will the new royal consort, Chae Kyung, from a common family, bring to this battle for the throne?
