Seventeen-year-old Artyom is invisible in the family and a rebel in the technical college. He has a best friend, Kostya, and they do together all provocations and tricks. When the administration of the college makes an unofficial list of dangerous teenagers, so called «explosives», Kostya, by pure chance, gets the first place, which makes him popular among other students. Kostya takes an interest in himself and betrays his friend, convincing his classmates that he, Kostya, is the main and the only inspiration for all their tricks. Then Artyom decides to prove who is actually, «the number one bomber». But along the way, a girl, Kira, unexpectedly appears who is able to influence his dangerous plan.