Despite Youn Ga Min's (Hwang Min Hyun) natural gift in martial arts, he dreams of academic success. However, the school he attends is notoriously attended by troubled students, making it difficult to succeed, and carries dark secrets – including a past teacher's murder. Determined to boost his grades, Ga Min forms a study group with Kim Se Hyun (Lee Jong Hyun) and other like-minded students, but the group soon finds itself targeted by bullies, led by Pi Han Ul (Cha Woo Min). Ga Min refuses to let his study group get beaten down, unleashing his fighting skills to defend them. Idealistic teacher Han Kyeong​ (Han Ji Eun), Ga Min's former tutor, also wants the school to do better, but she harbors some secrets of her own. Can Ga Min and Han Kyeong help this disastrous school?