Jung-gu crafts explosive devices and sends them to individuals who might use them. He teams up with Hyo-min, the first person to actually set one off. However, Hyo-min’s impulsive behavior provokes Jung-gu’s violent instincts, which he has struggled to keep in check. Ultimately, Jung-gu loses control, murders the detective pursuing him, and sets up Hyo-min to take the blame for all his misdeeds.