Welcome to a world where doppelgängers wield a grim duty: eliminating their human counterparts. In this twist of fate, a devil named Joon experiences a momentary lapse, inadvertently giving birth to Doh Seong-ah. Intended to replace Lee Woo-yeol, Seong-ah emerges with an unexpected twist – he resembles Joon’s cherished idol in male form. Unfazed, Seong-ah ventures into the human realm, driven by his mission.
However, the real challenge arises when Seong-ah confronts Woo-yeol, who proves to be a formidable and unexpectedly fearsome adversary. The question that looms large is whether Seong-ah can accomplish his mission and eliminate Woo-yeol, or if this world can accommodate the existence of both of them. In a tale of doppelgängers and unexpected alliances, the answer remains shrouded in mystery.