Cheer Up, Mr. Lee

Cheol Soo has a perfect appearance, but he is a bit slow. One day, his daughter Saet Byeol appears in front of him. Saet Byeol has been sick and she has been in the hospital. They start on a trip.
Chul-soo is a man with an intellectual disability. One day, Chul-soo finds out that a young girl, Saet-byul, who is in hospital is his daughter. And soon, Saet-byul sneaks out of the hospital and travels by herself to a faraway city for her friend's birthday. As Chul-soo accompanies Saet-byul's journey, friendship develops between the two.