Samantha inherits a rural house in Sader Ridge from an estranged aunt and invites her friends Mark, Caitlin, and Roman to come along. A neighbor named Eric, a young army veteran who knows the area, meets them and gives Sam a tour of the property. He ends up joining them on their first night at Sader Ridge, sharing stories about the house and revealing that Sam was born there and spent the first five years of her life in the same place—a memory that apparently does not belong to her. Eric also mentions that her aunt died in the house, a fact that casts a quiet shadow over the arrival.
The next day, the group sets out to explore the expansive property and its surroundings while Eric remains at the house. As evening approaches, Mark disappears from sight, and Caitlin, who has a crush on him, urges everyone to search for him. Eric volunteers to help, leaving Roman and Sam at the house to wait. Sam dozes beside Roman, and when she wakes to the screech of her car alarm, Roman is nowhere to be found. She goes outside to silence the alarm, then returns to find Roman on the front steps in a dazed, panicked state. When the others arrive, Sam tries to calm him, but it becomes clear that Roman was never really there. He later reappears in the living room as if nothing happened, while the rest of the group looks on in confusion.
The following day brings another twist: Mark and Caitlin head to the garage to investigate sounds they heard earlier, and Sam, hearing something that unsettles her, mistakes Mark for an attacker and strikes out in defense of Caitlin. Roman soon discovers that Mark and Caitlin were secretly together, a revelation that fuels his jealousy because he also likes Caitlin. That night, Sam is awakened by shouting from the next room. She checks and finds Mark violently beating Caitlin, then Mark turns on Sam, shoving her out of the room and slamming the door behind them. Sam runs to find Roman, only to discover that he is in hysterical tears, and to her horror, she finds Mark, Caitlin, and Roman all lounging in the living room later, casually drinking beers as if nothing had happened. They help Sam back to bed and begin to speculate about what to do next.
In the early morning, Sam is haunted by a nightmare in which Mark acts as a harsh father figure, punishing her with cigarette burns. Eric, who has been watching over her, explains more about Sam’s troubled past when she mentions the nightmare. The tension in the house brews as Roman and Mark argue outside after Caitlin and Mark have stayed up all night drinking. Roman drives away in their car, but before he disappears from view at the gate, Eric steps forward, offers to open the gate, and then unexpectedly pulls a hunting knife and stabs Roman several times before slipping away into the trees. Sam searches for Eric and discovers their car instead, with Roman lying bloodied in front of it.
Moments later, Eric appears again inside the house and confronts Sam with a grim calm as she processes the scene. Mark and Caitlin become victims of Eric’s violence: Caitlin is attacked as Eric cuts her throat and disappears into the woods, while Sam returns to the house and finds Mark standing over Caitlin’s lifeless body. In a conflicted moment, she stabs Mark, believing he has killed Caitlin, and Eric then consoles her as she breaks down.
Eventually, an officer arrives and asks about the four missing students—Mark, Caitlin, Roman, and Sam. Eric claims he has not seen any of them and sends the officer away, then returns inside the house where Sam greets him and they share a kiss, leaving the broader situation open and unresolved.
