Dynamite man (2013)

Two brothers try to break free of the gang life, only to be attacked in retaliation for their decision. The younger brother is seriously burned and dying in a hospital, which drives his older brother to take vicious revenge. In the course of his cruel actions, the enraged brother kills the gang members one by one by tying dynamite to their bodies and detonating it. Just before the end of the revenge, Jeok-San meets a father who spent childhood together with him and his brother. They talk for a long time, Jeok-San gives ashes of his brother, asks a last favor, and leaves for the last revenge. When Jeok-San kills the boss, Jeok-son becomes a pure darkness which is far from the humanity.