Beneath a neon-soaked city, Organization X uses cruel and bizarre methods to punish those deemed “beyond redemption,” leaving the police helpless. Detective Captain Gu Nanjue is at his wits’ end trying to crack the case, unaware that the quietest officer by his side, Mo Chi, is the one wielding the blade in the darkness. Behind his timid, obedient facade, the young man hides a ruthless obsession. When his mask comes off, Mo Chi declares that “darkness must be broken,” while Gu Nanjue holds fast to the belief that “the law must never yield to lawlessness.” A brutal clash over the meaning of justice erupts on the line between law and vigilante vengeance.