Shen Yiyi is an ordinary cook from the market. In order to repay a debt, she agrees to substitute for her good friend in marriage and travels to Chang'An in her stead. Along the way, she ends up in disguise as a gentleman and meets Yang Zi'an, a young man carrying out orders from the King. She also meets the sweet second prince Li Xinyuan, the high and mighty swordsman Dugu Muxue and the handsome flower boy Tang Jiuhua. In their pursuit of education, the five who bear secrets of their own learn to trust each other and become friends, thus embark on an exciting school life that brings them face to face with a mysterious case and corrupted officials