As Jackie begins to acclimate to her new life at Havenhurst, an ominous gothic apartment complex in the heart of New York City, she receives a stern warning from the mysterious landlord, Eleanor Mudgett, and her son Ezra, the building's maintenance man. They caution her to stay sober if she wishes to avoid eviction. However, this ominous advice only fuels Jackie's curiosity, especially as she unravels the sinister past of her friend Danielle, a former tenant whose brutal fate remains an unsettling mystery.
As Jackie navigates the winding corridors of the complex, she encounters a variety of characters, including Sarah, a troubled teen who endures the harsh reality of living with her abusive foster parents, Tammy and Wayne. The disturbing nature of Wayne's behavior quickly becomes apparent, but it is Paula who meets an especially gruesome end at the hands of a hidden killer.
Determined to uncover the truth behind the mysteries enveloping her, Jackie reaches out to her friend, Detective Tim Crawford, sharing her findings, including an unfinished map that Danielle created prior to her tragic death. This map serves as a key to revealing Havenhurst's true essence: an ordinary facade that conceals a multitude of buried secrets. Sarah, who has become increasingly close to Jackie, offers another vital piece of evidence in the form of Danielle's camera, which holds footage that exposes the dark reality lurking within the complex.
As tensions mount, Jackie becomes more fixated on understanding the identity of Jed, Eleanor's other son, who is a serial killer cleverly camouflaged behind a guise of normality. His sinister activities appear to correlate with those who have received eviction notices, ultimately claiming Tammy as one of his victims. In her frustration over Tim's disbelief and the absence of concrete evidence, Jackie succumbs to drinking, hoping that receiving an eviction notice might unlock the complex's hidden truths.
When Sarah moves in with Jackie, she stumbles upon a concealed passage in the laundry room that leads to a shocking discovery: Eleanor and her sons are direct descendants of H.H. Holmes, the infamous serial killer, and they have inherited his murderous instincts. The true nature of this family is revealed as they relentlessly pursue Jackie and Sarah, leaving no path for escape.
In a moment of desperation, Jackie reaches out to Tim for assistance, but it may be too late. When Sarah is captured, Jackie finds herself alone to fend off her ruthless tormentors. Despite her courageous attempts to survive, she is ultimately cornered by Eleanor and her sons. Just when hope seems lost, Tim arrives with a cadre of police officers, only to find no signs of wrongdoing, leaving him impotent in the face of the horror unfolding inside the apartment complex.
In the aftermath of this harrowing ordeal, Sarah is coerced into aligning herself with her captors, forever altering the course of her destiny. The malevolence that permeates Havenhurst has claimed all who dared to step beyond its gothic threshold.
