Silent House (2011)

A young woman named Sarah is staying at her family's dilapidated Victorian house in the countryside with her father John and her uncle Peter, helping them fix it to be put up for sale. After a petty argument between John and Peter, Peter leaves and drives into town for extra tools. Sarah meets a young woman named Sophia at the front door. Sophia claims to be one of Sarah's childhood friends, though Sarah does not remember her.

Soon after, Sarah panics when she hears John falling down the stairs. She tries to leave the house but all exits are blocked, and she hides from an unknown perpetrator. She finds John unconscious with a head wound and runs to the basement in search of the cellar door that leads outside. She finds a bed and other evidence that someone else has been living there, possibly squatters. She sees a figure searching for her and escapes out the cellar door.

Outside, she meets Peter, who has returned, and sees a young girl on the road who disappears. Peter and Sarah discover John's body missing in the house. When the power is cut off, the only light source available to them is the flash on a Polaroid camera. Through a series of camera flashes, Sarah sees the young girl and a man in the room. The power returns to reveal Peter missing. Sarah hides while two men take pictures, presumably pedophilic in nature, of an unseen girl. Sarah tries to shoot one of the men with Peter's gun, then hides in her room and begins to show signs of paranoia and psychosis. She experiences hallucinations of traumatic childhood events, including a bloodstain on the bed and the young girl in the bathtub with beer bottles and bloody water.

Frightened, Sarah flees and runs into Sophia. John, now conscious, is wrapped in plastic and sitting in the living room. Sophia gives Sarah a key to a box containing pedophilic pictures of Sarah as a little girl, implying that John sexually abused her. It is suggested that her recent interactions and hallucinations with the little girl and mystery attacker have been a traumatic repressed memory. Events at the house have caused this memory to reappear, and Sarah is now exacting her revenge. She has been confusing the events of her childhood with what she is doing now, likely due to dissociative identity disorder. She assaults John and Peter in her "intruder" mode while simultaneously wandering the house as a victim trying to escape.

The "intruder" drags Peter into the living room before it is revealed that it's actually Sarah herself. Sophia also turns out to be a figment of her imagination. John convinces Sarah to untie him, then whips her with his belt. Peter tries to stop him but John mocks Peter's pleas. As his back is turned, Sarah bludgeons his head with a sledgehammer, killing him. Peter begs for mercy and tells her he should have stopped the rape and abuse from the hands of John. Sarah leaves him and walks out silently. Peter’s fate in the aftermath remains a mystery.