Along a narrow road in the deep woods, Kathy (Zoe Kazan) is driving her 10-year-old daughter Lizzy (Ella Ballentine) to her father's house as it's his turn for custody. Tired of taking care of her abusive, alcoholic mother, Lizzy makes it clear she wants to live with her father permanently. As night falls, Kathy hits a wolf with her car. However, its injuries look like they were sustained by an animal attack rather than their car. Because Kathy was injured in the collision, Lizzy calls a tow truck and ambulance.The tow truck arrives and its driver, Jesse (Aaron Douglas), begins working underneath the car. Lizzy notices that the wolf's body is missing and becomes frightened. Tired of bickering with Lizzy, Kathy gets out of the car to talk to Jesse but cannot find him. Suddenly, Jesse's severed arm lands on the hood of the car. In agony, Jesse crawls out of the woods, but before Kathy can help him, a monstrous creature drags him under the tow truck and eats him.Attracted by the sound of music emanating from Lizzy's teddy bear, the monster attacks the car, dragging Kathy out. But before it can kill her, it is temporarily scared away by the approaching ambulance. As Kathy and Lizzy cower in the ambulance, the monster kills the EMT team. Kathy tries to drive away but when the monster attacks the ambulance, she swerves into the woods.Kathy begins vomiting up blood and realizes she has internal bleeding that will likely kill her soon. Now aware that the monster is scared away by bright light, Kathy uses her lighter to make a torch and tells Lizzy her plan. She's going to run into the woods so the monster will chase her and Lizzy will run to the road to get help. She tells Lizzy she is the best thing in her life.Thinking that Lizzy is running to the road, Kathy allows herself to be attacked by the monster which claws her throat out. Lizzy, who has refused to leave out of pure fear, attacks it with a hammer and chases the monster away with the flashlight. Realizing her mother is dead, Lizzy lures the monster to the ambulance where she uses a spray can from the ambulance and her mother's lighter to set the monster ablaze, killing it. Then after a final twitch from the creature, she batters it with a large stick.In a short flashback, Lizzy remembers how, after a particularly hateful, alcohol-fuelled encounter, Kathy had apologized and predicted that Lizzy would grow up to be a better person than she was. As the sun rises, Lizzy emerges from the woods.