In a tense, claustrophobic home-invasion tale, a quiet family vacation becomes a deadly battleground when masked intruders descend on their secluded house. The night begins with a shocking eruption of violence at the Bronson home: Jim Bronson orders his wife Maggie Bronson to check outside after hearing strange noises, only to watch their dog die and then be killed himself. The danger escalates as the intruders slip upstairs and brutally assault Mary Bronson, the couple’s young daughter, leaving a house full of fear and unanswered questions.
Cory Morgan, his wife Sarah Morgan, and their seven-year-old son Liam Morgan Peter DaCunha arrive at a remote vacation retreat, still grieving Liam’s birth mother. The atmosphere is tense as Liam keeps his distance from Sarah, seemingly resistant to accepting her as part of the family. The Morgans move through a house that looks abandoned and neglected, discovering plates of rotten food and used linens, revealing that squatters may have taken refuge there. They contact Officer Hawkings Stephen McHattie, hoping for reassurance, but he explains that there is little he can do about a breaking-and-entering in such a remote location, even as he hands Sarah his card to help ease her nerves.
That night, eerie noises echo through the house and Sarah realizes Liam is missing. In her search outside, she mends a painful wound from stepping on a nail. The tension rises when they find Officer Hawkings tied up in his patrol car, which suddenly explodes as a mouse-masked intruder watches the flames from a distance. With Sarah injured, Cory must venture to the nearby Bronson residence for help, leaving Sarah behind. Inside the Bronson home, Cory discovers a brutal crime scene and is then seized by a pair of masked assailants—one wearing a mouse mask and the other a rabbit mask—before being knocked unconscious.
The intruders reveal themselves as a quartet wearing masks cut from Liam’s oversized stuffed animals: Mr. Mouse, Pig Lady, Little Rabbit, and Little Monkey. The tension intensifies as Cory awakens to a sadistic welcome: Mr. Mouse tortures him with a car battery, and the group drags Liam into their orbit as they force Cory to confess that he does not love his own son. Liam’s screams reverberate as Little Rabbit hauls him away. Mr. Mouse proclaims, “He is part of our family now,” as a plastic bag is taped over Cory’s head and he is left to suffocate.
Back at the Morgan residence, Sarah is pursued by Pig Lady, but she manages to escape and ultimately drowns Pig Lady in a forest creek after a brutal struggle. Cory, meanwhile, frees himself from restraints and finds Liam, assuring his son that his harsh words were the product of torture, not truth. The reunion is interrupted when Little Monkey, confronting them with a pitchfork, is unmasked—revealed to be Mary Bronson herself, brainwashed by the intruders. Cory knocks her out and escapes with Liam into the forest, determined to protect his family.
Mr. Mouse captures Sarah again, and Cory hears her screams as he hurries back to rescue her. Sarah shocks Mr. Mouse with the electrified car battery and escapes once more with Cory. The pursuit continues as Little Rabbit emerges with a rifle, fatally shooting Cory as Sarah and Liam flee through the trees. In a final, desperate struggle, Sarah confronts the masked killer and, with the gun emptied, manages to subdue Little Rabbit.
The aftermath finds Mary Bronson being taken away by police in a squad car, while an ambulance carries Little Rabbit. A suspicious crack in the windshield is followed by a brutal end to the officer who pulls the vehicle over, killed by Mr. Mouse with a rock. He retrieves his mask from an evidence bag and climbs back into the driver’s seat as Mary mutters that she knew he would come for her; his chilling reply hints at a terrifying purpose: “We must find you a new mother.” She asks about the father, and he coldly states, “The father will be coming.” In a final, disturbing twist, Little Rabbit unshackles himself from the gurney, unmasks, and reaches for a scalpel, ready to murder the ambulance driver as the story closes on a note of unresolved menace.
