11 parts Complete A young couple moves into an apartment in an older, residential building in Seoul. The apartment is affordable, and everything seems fine until they start hearing strange whispers at night. The whispers seem to be coming from the walls themselves-soft, unintelligible voices that occasionally call out their names. At first, they dismiss it as the noise of old plumbing or the building settling, but the whispers become clearer over time, speaking of forgotten tragedies and people who lived in the apartment decades ago. The couple begins to uncover secrets about the building's history: it was once a site for military interrogations during a time of political unrest, and the spirits of those tortured there seem to be trapped within the walls, seeking revenge. As the couple investigates further, they begin to experience more disturbing phenomena-visions of the past, hallucinations, and even physical attacks from unseen forces. They must uncover the truth of the building's dark past before it consumes them too.
