This is a story of revenge, the roots of which stretch back well over twenty years. Park Moo Yul was a loyal soldier, held in high regard by all, who was killed during a secret operation in North Korea because of the very government he served so faithfully. What nobody knows is that Park Moo Yul, along with 20 of his comrades, was not the victim of a tragedy, but rather of a betrayal by those who sent the commando unit on the mission. Naturally, this was never revealed publicly, and the 21 victims were declared missing and then forgotten. However, this story left behind one witness; Lee Jin Pyo, a comrade of Park Moo Yul who survived thanks to his friend’s sacrifice; as he lay dying, Park asked him to look after his family, including his infant son. It was from this point that this man’s anger turned into a burning desire for revenge. Upon his return from North Korea, he abducted the young Lee Young Sung, Moo Yul’s son, made him his own son and subjected him, from a very young age, to gruelling and ruthless training, turning him into a killing machine.