Invincible

In Busan, South Korea, the powerful arms traffickers Kim Hyeok and Yeong-choon are best friends. Hyeok has spent many months seeking out his younger brother Kim Cheol that was left behind by Hyeok with their mother while escaping from North Korea. When Hyeok finally finds Cheol, his brother blames him for the death of their mother that was beaten to death in the prison and keeps distance from Hyeok. When Hyeok travels with the gangster Tae Min to Thailand for a negotiation, he is betrayed by Tae Min and is arrested by the police. Meanwhile Cheol joins the police force to become a detective and Yeong-choon kills the gang that betrayed his friend. When Hyeok is finally released from the Thai prison and returns to Busan, he finds that his brother is a detective investigating Tae Min and Yeong-choon limped and in complete misery. But Hyeok promises that he would not return to life of outlaw. But he is haunted by his past and the need of protecting his estranged brother.