Kim Ki-bum

 Park Ye-jin

 Yang Jin-woo

 Joo-bi

14-year-old Geum Eun-dong (Kim Ki-bum) is desperately in love with Lee Tae-ri (Park Ye-jin), a well-bred heiress who is seven years older than he is. Eun-dong's wish is mysteriously granted when he wakes up to find that he's become a handsome 25-year-old man: the perfect contender. As Tae-ri's new assistant Hwang Min-soo, he learns of Tae-ri's heartbreak and discovers that not everything is as it seems in her picture perfect life.