Jin-cheol, a cab driver in Seoul, cannot take any passengers because his last customer left his guitar in the backseat. Annoyed and angry, Jin-cheol heads over to a guitar store.

A mother, Soon-hee, and her son, Hae-seok, lived in a village for a long time. One day, they are told that sea levels have risen and that they have to leave the village. They begin to learn how to swim together to stay in the village. Meanwhile, Soon-hee's friend Bok-young gives Soon-hee something to help her swim...