During the Japanese colonial era, roughly 400 Korean people, who were forced onto Battleship Island 'Hashima Island' to mine for coal, attempt to escape.

Whenever elementary school teacher Kang Joon-soo falls in love, he always gives too much of himself to the relationship. Yet despite that, he ends up being the one getting dumped by his girlfriends. Joon-soo has been friends for 18 years with Kim Hyun-woo, a weather forecaster whose beauty belies her witty tongue and aggressive manner.

Han-gu was born to a Pilipino father and a Korean mother. His dream is to become a national Taekwondo athlete, and he's usually very bright and cheerful. His girlfriend Mi-su always encourages his dream. Maybe his dream was too fantastical; he always fails to make it to the final round, and it's not just because of his talent. However, Han-gu doesn't give up and doesn't show any sign of exhaustion. He challenges himself to become a national Taekwondo athlete for the sake of his family and his girlfriend. Can he become a national Taekwondo athlete?