Plot summary

Ben goes to visit his father, Liam, in a little coastal town. He got a plaster on his left arm, but it does not keep him from working with his father on a marina. There she meets Mallory, and they connect since the beginning. Ben's house is next to a young couple. Her neighbor, Abby, and his son, Dillon, go hiking and the boy sees something strange. A tree with a hole at the bottom, and from the inside he starts hearing his mother with a creepy voice. He gets frightened, but his mother arrives and they both go home. Her husband arrives as well later with another son-a baby-and he sees in Abby's pick-up truck the legs of a dead deer dripping blood. She guts the deer with his son, but late at night a strange creature woman like emerges from the deer and starts hunting her house.The next night while Ben is on a party with Mallory the woman wakes up because her baby is crying but before entering the room he gets quiet. She lies on the bed again watching a baby TV monitor. Unknowingly to her, the creature is there watching the baby in silence, but because it is dark, she hides in the shadows next to the crib of the baby. Minutes later, Dillon comes to his parent's room to sleep with them. When the woman looks again to the TV monitor, she can not seem his baby, so she goes to the baby's room. When she arrives she sees him covered in a blanket and when she lifts the blanket the baby is not there. In his place there are a bunch of branches. Slowly, from under the crib, some gloomy substance starts to advance to her. Seconds later, the creature takes the woman from her ankles and drags her under the crib.When Ben arrives from the party late at night, he sees the woman going alone into the woods, and she seems to be carrying something in her arms. When she disappears in the darkness, Liam arrives with the car, and they have a discussion because Ben was supposed to have dinner with him and his girlfriend Sara. The next morning, Abby's husband wakes up alone in bed, and he is running late. The kid is watching TV while the creature is looking at him. At his point it is clear that the woman is not her mother anymore; she walks awkward, she stares a lot at his son and through the window, etc. That night, Sara takes home Ben from the marina as they fix things. Before leaving the marina, Ben is watching a series of pictures in a board, and he observes one with Mallory, her mother and her little sister, Lily. When Ben enters the house he hears some noises, and he is surprised when Dillon is there hidden and scared. The woman arrives and ask for her son, but Ben decides not to tell her he is there. The father arrives then, his son goes down the stairs running to him.Things go quiet until the next day, when Ben is waiting in the marina for Dillon to give him some classes, but he does not show up. Ben goes to his neighbors' house and the father opens the door. When Ben asks the father where is Dillon, he is shocked because he does not seem to recognize that he has any kids. After the conversation, he sees a symbol-some kind of inverted A-under the rug of the house of his neighbor. He performs an Internet search, and he finds pictures and texts about a black creature with bright white eyes which seems to feed on the forgotten ones and who, apparently, is able to wear people like suits. Later, he invites Mallory home, and they watch Abby getting stuff from her cellar and throwing in on the garbage can. When Ben tells Mallory everything that has been going on, before leaving, she passes a note with a picture of a witch under the door of Abby. While he has been seeing Mallory leave, the creature posing as Abby has been watching him from her house. Moments after, her husband asks her if kids has been next to the cellar door, Abby approaches him, she whispers something in his ear, and he stays there, still, bleeding from the ear. That night, Sara is alone in the marina and the creature is observing her from outside the window. At that precise moment, Mallory arrives to lock up the office. She starts hearing noises, but she does not give it importance, so she closes the door and leaves. At the moment she leaves the place the camera shows the board, the picture of her, her mother and her sister is not there anymore. The next day, Ben goes to the cellar from where Abby emerged with a plastic bag and there he sees a series of pictures: one of the family with the kids-his neighbors-but the face of the father has been crossed out and the one with Mallory and her mother and her sister with the faces of the two firsts crossed out. He calls Mallory to ask about her sister, but Mallory does not remember having any sister. He goes to the park where Mallory and her sister are, but when he arrives the creature has already taken Lily to the woods, Ben follows her until the tree with the hole on the bottom. Nevertheless, the creature is too strong and achieves to make her disappear in the hole before Ben could hold her and get her out. When he loses grip of her, he falls backwards, and he hits the base of his skull with a stone. When he wakes up, it is nighttime, and he goes home, but the police is there because of the trespassing of the cellar. Sara is there too and at a given moment they are alone, and he realizes that she is the creature now. They have a fight, and he cuts her with a knife, the father arrives, but the creature is already posing as Sara. The police takes Ben to the station and from inside the car he can see how Sara whispers something to the police. Before leaving, Ben tells Liam to look on the cellar. On the way to the station, Ben sees the police men bleeding from his ear. The latter stops the car to attack him, but he escapes. Liam wants to go to the station, but before leaving decides to check the cellar of Abby. There is nothing there, but when he is about to leave, he sees Abby's husband going into a room from outside the house. Liam enters a penthouse, and he founds there a sort of altar with pictures on it and the bodies of Abby and her husband dead. When he is checking one of him with her ex-wife and Ben with the three faces crossed out, the creature stabs him from behind, but he manages to escape, not before inflame the altar by accident.After a fight, Ben arrives and shoots Sara and the creature emerges from her abdomen. They get to the car while the flames start to spread burning the picture of Liam, Ben, and his mother but now there is another child in the picture. Through flashbacks a couple of scenes show that he had a little brother, the one in the picture, that was almost always present, but they have forgotten him too; in the bus at the beginning of the movie, while they take diner outside the house, etc. He tries to get Nathan, his brother, from inside the house, but the creature has already taken him to the woods. At that moment, Mallory arrives, following him to the base of the tree. He ties up himself to a tree, so he can escape, and he spreads some gasoline over the tree. Ben tells Mallory that if in ten minutes he does not come up, she must burn the tree. Inside the hole he finds Lily, Mallory's sister, and after a fight with the creature, Nathan. He manages to get them out. When everyone is outside the tree the creature emerges and takes Ben by his ankles, Mallory throw salt in the eyes of the creature and Liam arrives with his car and smashes her against the tree.The next day, Mallory is talking to a counselor, she says to her that Lily told her that they had to burn the tree, but the counselor does not know what her little sister is talking about. Apparently, not everybody could see the tree. Mallory decides to tell her that it was probably a nightmare. Later, she and Ben are saying their goodbyes and kiss each other. Then Mallory goes in a boat with a bunch of kids to teach them how to navigate. Before leaving, Mallory gives a flower to Ben, and when he is in the car he realizes that it was a plastic flower, so it could not decay, apparently when the creature haunted a place all the flowers decayed. He is visibly shocked, and the last scene shows Mallory away from the marina in the boat with the kids. She is staring without any facial expression to the camera while the kids are talking to each other, oblivious to her behavior.