As a child, Masaki Sata was teased and bullied because of his appearance and called “Demekin” (popeyed goldfish). He decided to fight back and eventually became unbeatable in fights. His red hair also became a trademark. Masaki Sata and his buddy Atsunari then spent their days fighting and riding motorcycles. After middle school, Masaki Sata went on to high school and Atsunari begins to work at a ramen restaurant. One day, Atsunari comes up with the idea of starting a motorcycle gang with Masaki Sata. What awaits for them are enemies.

故事发生在20世纪80年代，中学生三桥贵志（贺来贤人 饰）和伊藤真司（伊藤健太郎 饰）转学来到新的学校，为了看起来凶恶一点，他们不约而同改换了不良少年的打扮。刚刚入学，两人意外打倒十人，一战成名。此后他们结识了女校的戏精大姐大早川京子（桥本环奈 饰）、男校的大嗓门傻老大今井（太贺 饰）、今井的小跟班谷川（矢本悠马 饰）以及本校的功夫纪律委员赤坂理子（清野菜名 饰）。在与黑道分子和其他学校不良少年的抗争过程中，少男少女的友情不断加深，而爆笑沙雕的故事也接二连三的发生。三桥与伊藤的确度过了一段难忘的青春岁月…… 本片根据同名漫画改编。