Ordinary teen Kang Yoo (Dong Ho), who can’t get along with people at home or school, begins to learn the basics of boxing from a book. One day, he goes out on the street and defends himself with his new learned boxing skills from a group of thugs. Since that time, he is called the hunter of thugs. By chance, Kang Yoo meets Sang Ho (Sung Woong), who becomes his mentor. Kang Yoo pushes himself to find out who he really is …