Jay, the legendary hitman of the American underworld, is hired by Union—the largest assassination agency in North America— to dismantle the agency founded by his own friend, Johnny.

The condition for accepting the job was that Johnny’s life would be spared, but due to Union’s betrayal, both Johnny and Jay are murdered.

However, through a mysterious power, Jay is resurrected in the body of an ordinary young man in Korea. There, he reunites with Johnny, who has been resurrected in the body of a young woman. The two decide to join forces once again to seek revenge against the Union that killed them by founding their own powerful “Company.”