The president’s daughter, Yoon Jae-hee (Jun Do-yeon) is a Korean diplomat in Prague. She has only recently recovered from a devastating break up five years earlier with Ji Young-woo (Kim Min-joon), the son of a prominent Korean businessman. Choi Sang-hyun (Kim Joo-hyuk) is a detective who goes to Prague searching for his ex-girlfriend Hye-joo (Yoon Se-ah). Hye-joo broke up with Sang-hyun over the phone from Prague and Sang-hyun can not accept it.