Hot Young Bloods (2014)

Set in the 80s, a countryside high school teen named, Joong-gil, is the biggest heartthrob in town. Young-sook, the girlfriend of the school’s toughest bully, has a crush on Joong-gil, but he shows her no interest. One day, So-hee, an innocent looking girl, moves into town. Young-sook thinks So-hee as her rival and picks a fight with her. Meanwhile, Young-sook’s boyfriend suspects ties between Young-sook and Joong-gil and harasses So-hee, whom Joong-gil has a crush on. Joong-gil tries to get revenge for So-hee’s sake, but gets beaten down every time. At last, Joong-gil decides to have his ultimate battle of revenge aboard a running commuter train.