Five teenagers stained by all sorts of misdeeds. Detective Jung, believing that if someone could give them the love they desperately craved, they would have no difficulty adapting to society, decided to teach them Taekwondo to restore their humanity first. In their first Taekwondo match, without even knowing the rules, they committed fouls against their opponents and created a chaos, which resulted in their expulsion from the ring and Detective Jung receiving numerous reprimands and criticism from the association. Following this incident, upon discovering Detective Jung's brilliant career as a fighter, they knelt and promised to be reborn. Through hellish training that was difficult to overcome, they acquired the principles and energy of Taekwondo, and transformed through relentless effort. The Taeguk team, participating in a renewed competition, faced their most formidable rival, the Gyeongho team. The director of the Gyeongho team was Detective Jung's arch-rival during his fighting days. They now meet again as coaches, and under the audience's attention, the final decisive match continues.