After years of being bullied, Choi Baekho snaps one day and finds himself standing over his pummeled tormentors with bloody fists and gaps in his memory. Now, as Shinheung High’s “crazy dog,” he’s gnashing his teeth at all those who rely on the strength of numbers. But when his efforts to beat 11th grade’s top gun Do Changsoo get him mixed up with the mob, Baekho must join forces with his own rival. Can this unlikely ally help Baekho control his “switch” and become every bully’s worst nightmare?