In 1944, bandmaster Lee Gang-ok (Hwang Jung-min) and his daughter (Kim Su-an) are deceived and forced into brutal slave labor on Japan’s Hashima Island. Alongside gangster Choi (So Ji-sub) and captive Mallyon (Lee Jung-hyun), they face unspeakable cruelty. Eventually, covert independence fighter Park Mu-young (Song Joong-ki) orchestrates a massive, daring evacuation for 400 trapped Koreans.