The film explains the legacy of violence passed down through three generations. The lives of a murderous father, a son addicted to violence, and the victims of violence intertwine into a surprising finale.

Shot in Busan, Shadow Island is the name of a location as well as the main character's name. The film explains the legacy of violence passed down through three generations. The lives of a murderous father, a son addicted to violence, and the victims of violence intertwine into a surprising finale. As the film shifts through the past and present, it reveals a painful family history that eats away the soul and leads to a burdened fate of self-destruction.