I'll rewatch this again, cause I seem misunderstood the story, i didn't get at first at episode 1-9, while at episode 10 it makes sense all the episode haha! but since its a genre of psychological and thriller, at the end of the drama, its so brutal that makes me speechless that I didn't expect that would be happen. So the killer's soul are now on the protagonist? or he delusion of himself cause of the experience that he through from the studio. And why the police woman, she didn't make a statement that she knew who's the killer of the landlady, the other twin, the porn addict and the dentist.