After aimlessly hopping crime scenes for five years, detective Kang Cheol-jung (Sol Kyung-Gu) hands in his resignation in the face of major financial burdens. His chief, however, asks him to stay on until a high school murder case is closed. At first, it looks hopeless, but then Kang finds a fingerprint lead, and later learns that three of the dead student's friends are employed by a single company. He begins to investigate the group and its leader, Lee Won-sul (Jung Jae-Young).