Park Chan Yeol & Lee Eun is a very happy couple. Actually, they were friends, childhood bestfriends that is. But one day, Chanyeol, left Korea (Seoul) to study leaving Lee Eun. Or is it really studying? When he returned, he met Lee Eun but this time, she doesn't have a single idea of who he is. Chanyeol was shocked, he thought she was just mad at him. They said she met an accident gaining her an amnesia. This time whenever they meet, she just smiles but she doesn't know him anymore. She doesn't even remember her relationship with him. Chanyeol wants to court her again by doing everything for her to remember him. He did everything they use to do because he was hoping if they will do it again maybe she can remember him. Will Lee Eun remember Chanyeol and love him again? Or will she love someone else instead?