Kim Jiyong is a diligent and brilliant student at the police academy. However, during weekends, he assumes the role of a vigilante to apprehend wrongdoers who evade the reach of the law. His moves, which were given the name Vigilante by the broadcaster reporter Choi Miryeo, garnered the attention and cheers of the public, and Jo Gang-ok appears, a big fan and second-generation heir of a conglomerates. In response, Jo Heon, the leader of the Metropolitan Investigation Squad, initiates a pursuit of Vigilante.