Jong Woo moves into what appears to be a run down residence but nothing more than that. However, during his stay at this residence he encounters Moon Jo, a reserved dentist. When things start going sour between the people in the residence, and people are dropping like flies, going missing out of nowhere he can't help question whether the culprit is in between these walls.

Moon Jo x Y/N Story... A young girl is forced to move into Eden Residence after moving to Seoul, looking for a fresh start. After meeting Moon Jo, she finds out just how dangerous strangers can be, as her life is turned upside down. When Moon Jo's obsessive behavior begins to threaten everyone around her, will she be able to escape, or does she even want to?