Scarlet Heart: Ryeo is the remake of Chinese drama Bu Bu Jing Xin that stars IU as a woman who gets time-warped back to the Goryeo dynasty, and becomes involved with a very large family of princes, some of whom are vying for the throne, or her affections, or both.

It is about an ordinary girl named Ji Yeon hee who finds out that her neighbors are the lame dudes of EXO.