Chae-gyeong, an ordinary art high school student was told an unexpected news that, based on her grandfather's will, she must marry the unemotional Crown Prince Lee Shin who attends the same high school. She resisted the proposal, but reluctantly marries him to help her debt-ridden family. As she struggles to adapt herself to the proper manners and royal duties of palace life, Lee Shin's sentimental cousin and second-in-line to the throne Yul steps into her life. She feels like she can rely on Yul to help her.

The show depicts numerous delightful episodes among the cute and lively Chae-gyeong, the cold heartthrob Lee Shin, the handsome, down-to-earth Yul, the perfect ballerina Hyo-rin who just can't get over Lee Shin, and all the other members of the royal family. Through thick and thin, Shin had began to like her. But will he be too late to prevent Yul from taking her away? Will the Crowned Princess, Chae-gyeong have a happy ending with the Prince?