In a big city of Busan, twin brothers were left in the orphanage after the tragic death of their parents. Tae Ju, the older brother, becomes a cop, and Tae Sung, the younger one, holds a significant position in the local gang. Their ironic fate adds up to have both of them love the same girl, Chan Mi. As the feud between two different gangs surrounding the casino heats up, Tae Sung’sbest friend betrays him and places him in a trap. As police line approaches, Tae Ju comes to persuade Tae Sung to surrender but first, they have to face the truth about the traumatic incident which caused them to drift apart.