Jay, a legendary hitman in the American underworld, takes on a contract from Union—North America’s biggest assassination syndicate—to dismantle the firm founded by his friend, Johnny, with his own two hands.

The only condition he had for taking the job was that Johnny’s life be spared, but Union betrayed him. In the end, both Johnny and Jay were murdered.

But through a mysterious power, Jay is resurrected in Korea in the body of an ordinary young man. He eventually reunites with Johnny, who has been reborn in the body of a young woman. To get revenge on Union for what they did, the two decide to team up once more and start their own powerful “Company.”