18 Again describes the story of Hong Dae-young and Jung Da-jung and their pair of twins. Hong Dae-young was to be a rising basketball star until they struggled with their teenage pregnancy.

Dae-young (37) , facing difficulties in both his career and marriage, wished that he could become 18 years old again to choose a different life for himself. Being 18 year old body, how is he going to face his school going children and wife again?