After spending 7 years serving his boss, Sun Woo obtained his boss, President Kang's absolute trust. A cold-hearted boss, President Kang punished rule-breakers regardless of any mistakes they made. He had a secret that he cannot tell anybody: that is his young lover, Hee-Soo. President Kang orders Sun-Woo to watch her out of the doubt that she might have another lover, and if it turns out true, to kill her.
On the third day when Sun-Woo started following Hee-Soo, he made a surprise attack on the place where Hee-Soo was with her boyfriend. However, at the last moment, he let them go after much hesitation.
Sun-Woo believed that everything can return to the normal state. However, due to this decision that he has made, Sun-Woo starts an irreparable war against the whole gang who were his own brothers until the day he spare Hee-SooÂ’s life.