This drama is the perfect example of psychological thriller. Every single character is just perfect. The acting, the directing, the setting.......every thing is just amazing. The show might seem to be a tiny bit slow, but it's necessary in order to create the environment of fear and terror that the "good people" are making the protagonist and people around him feel. It's intriguing, and will keep your teeth gritted in excitement and suspense about what's going to happen next.........I literally binge-watched the entire show cause I just couldn't wait to see what happened next.
Honestly if you you've watched a lot other thrillers (like me), you'll be expecting Jungwoo to snap and finally murder someone, but still it somehow manages to take you by surprise by the way it happens. In the beginning, when we transition between Jungwoo's actual emotions and the emotions that he shows in real life, is something many people feel. Keeping up with irritating people and not bashing their head in the wall even if u feel like doing it, is the bridge between good and bad. We can see Jungwoo struggling between them and he first finally gives into it when breaks the keyboard of his fat senior. And then he just keeps snapping from sanity and insanity in such a intriguing manner, that it's hard to tell what he's gonna do next. This transition between his good and dark side makes his character even more unpredictable.
Even the antagonist, Moonjo is very unpredictable, as we don't understand whether he wants to kill Jungwoo, or make him a killer. He definitely finds Jungwoo interesting, as he and Jungwoo shared the same thought about killing a person. But still he never really approached him the same way as he did with the previous tenants. For others he pulled out their dark side and told them that their was a beauty in just showing your emotions bluntly. In other words, if u feel like killing someone, just kill him/ her. For Jungwoo he was just adding fuel to the fire, until the fire finally exploded. He just shortened Jungwoo's bridge between his desires and actual doings, until the bridge finally disappeared.
Sorry got really carried away........this review is long but I hope it helps.
Peace!