Two spies share a secret bond, despite their loyalties. A North Korean assassin is sent to Seoul to kill a dissident, but instead he teams up with a South Korean agent in search for revenge.

A coldhearted heiress, a man from her past and an ambitious new hire in her company all become entangled on a battleground for money and power.

Kyung-chul is a dangerous psychopath who kills for pleasure. Soo-hyeon, a top-secret agent, decides to track down the murderer himself. He promises himself that he will do everything in his power ...