Kang Bok Soo was expelled from high school after being falsely accused of violence by his first love, Son Soo Jung, and fellow student Oh Se Ho. The betrayal changed his life, leaving him to struggle as an adult with nothing going his way.

Years later, Bok Soo returns to the same high school, not as a student—but as part of a plan to get revenge. However, things don’t go as expected. As he gets caught up in a series of surprising events, he starts to realize that revenge might not be as simple as he thought.