The Siren.

Manager Oh, an employee at a noise pollution treatment center, takes his own life after suffering verbal abuse by local residents demanding a huge amount of compensation. Amid public criticism of regional self-centeredness, Taeseung joins the center as his successor. With his heart set on getting promotion, Taeseung immediately goes around asking for signatures. As the local residents cooperate in order to avoid further public criticism, the promotion seems to be just around the corner. However, when Youngsik and Donggyu get in the way, Taeseung suspects that they may have killed Manager Oh.