One day, Yeon-gyu ends up fighting to protect his younger sister, Ha-yan. In desperate need of money for the settlement, Yeon-gyu receives help from Chi-geon, and this becomes the turning point that leads him to start a new life in Chi-geon's organization. Although fearful and inexperienced, Yeon-gyu begins to follow Chi-geon, who is like an older brother to him, and gradually adapts to his new life. Gaining Chi-geon's trust, Yeon-gyu starts to get drawn deeper into increasingly dangerous situations as he strives to survive in the world of the organization…
