The individual known as Chul-soo has an intellectual impairment. Chul-soo learns one day that a young girl named Saet-byul who is now being treated in a hospital is actually his daughter. And not long after that, Saet-byul escapes the hospital undetected and makes her way all by herself to a distant city in order to celebrate her close friend's birthday there. Chul-soo and Saet-byul become friends during the course of Chul-soo accompanying Saet-byul on his tour.