Scan Doll: Katsumi, a man who lives a lazy and uninspired life, suddenly becomes addicted to "peeping" to uncover the true identity of his unknown neighbors in the same apartment building, i.e. their abnormal daily lives. In the midst of this, a mysterious high school girl named Mika suddenly jumps into Katsumi's eye. In order to find out what's going on with Mika, who regularly comes to the room of a middle-aged man with no luck, Katsumi uses his high-tech skills to peep into the girl's life, but he soon becomes obsessed with the girl's mysterious charms. What is Mika's true face that he finally sees?