Undercover police officer Ja-sung (Lee Jung-jae) infiltrates Gold Moon, the biggest crime organization in Korea, to investigate them under the command of his superior Kang (Choi Min-sik). After eight years, Ja-sung becomes the right-hand man to the ring's second-in-command Jung Chung (Hwang Jung-min), who holds the real power. But when its leader is killed in a mysterious car accident, Gold Moon is thrown into chaos and power struggles that threaten to tear it apart. Top-level police officials initiate project "New World" to intervene in Gold Moon's selection process for the next leader, and to use the leader's death to their advantage in controlling the crime organization. Caught between Jung Chung who trusts him with his life, and Kang who thinks of him only as bait, Ja-sung is cornered by both bosses on opposite sides and must make a final decision that rests on loyalty and betrayal.