In the dark days of the early 1980s, three high school students: Hae Jeok, Bong Pal, and Seong Gi, are spending their youth quarreling. One day, Hae Jeok is walking down the street after a gang fight when he happens to see the beautiful Bong Ja. He falls in love with her at first sight, but even though he excels at fighting, his shyness around girls prevents him from saying a word.A few days later, Bong Pal stops coming to school, so Hae Jeok and Seong Gi take a walk up to his home. There they find a family picture, which unexpectedly includes Bong Ja. Incredible, Bong Ja is sister to the stupid Bong Pal! They learn that Bong Pal has stopped coming to school to earn money for his family, and what is worse, Bong Ja has started working at a local saloon. The trio, led by the courageous Hae Jeok, invade the saloon, but Bong Ja has already been passed over to a disco bar named Hwang Jae. Although the thugs at the saloon were no problem for our trio, they are defeated by the gangsters at the disco bar. The boss of Hwang Jae makes an unexpected proposal to the brave Hae Jeok. If he can triumph and become a King of Disco at their upcoming disco contest, Bong Ja will be released. But only a week remains, and Hae Jeok doesn't know the first thing about dancing.