Live life to its fullest! 23-year?old Sang Doo (Rain) shows us his way to live his life to the fullest even in times of adversity. Sang Doo was put in jail for fighting with a man who tried to pick on his first love, Enhwang (Kong Hyo-jin). Having a sick daughter, he makes money to settle the medical bills by working as a toyboy and going out with rich women. One day, when he runs into Enhwang again, he knows deep down that she is the one he has been waiting for in life. To approach Enhwang, Sang Doo begins to work as a custodian in the school she works for…

KBS TV series hit "Sang Doo! Let's go to school" starring K pop singer Rain and Kong Hyo-jin from MBC's TV series "Snowman" brings you a hilarious drama of life and love.