Rural Texas, 1979
Sheriff Dentler (James Gaylyn) arrives at the scene of a horrific crime. There is a corpse covered up in the front of the house, and blood splattered all over the front porch. As Dentler goes inside, the deputy tells him to go inside the house to see something particularly gruesome, and Dentler is left stunned.
One Day Earlier....
Aspiring starlet Maxine Minx (Mia Goth) is getting ready to go down to Houston, Texas to shoot a porno film titled, "The Farmer's Daughter". Her boyfriend, executive producer Wayne (Martin Henderson), brings her along with the rest of the crew - writer/director R.J. (Owen Campbell), his girlfriend and sound operator Lorraine (Jenna Ortega), and actors/couple Bobby-Lynne (Brittany Snow) and Jackson (Scott Mescudi). Wayne refers to Lorraine as "Churchmouse" because he sees her as more prudish than the others, and Bobby-Lynne and Jackson make out on the way there.
The crew arrives at the farmhouse where they are set to shoot the film. Wayne goes to talk to the elderly owner, Howard (Stephen Ure), who greets him with a rifle pointed at him. Wayne has to remind Howard that they spoke the other night about renting his place out, but once Howard notices the rest of the crew, he makes it clear that he does not like or trust any of them. While Maxine gets out of the van, she notices Howard's wife Pearl (also Mia Goth in a dual role) watching her from the window.
Before filming begins, Maxine meets Pearl, who appears to try and make a pass at her. Pearl talks about her age and laments how she and Howard have not been intimate for a while.
The crew gathers in the farmhouse, where the first scene has Jackson and Bobby-Lynne have sex, the premise of the film being that Jackson's car broke down and he comes upon Bobby-Lynne's house and propositions him before they film their scene. The next scene has Maxine playing the younger sister who also has sex with Jackson. Pearl watches the scene going on and appears to get aroused. She tells Howard she wants him to make love to her, but he declines since he feels his heart cannot take it.
That night, Lorraine tells R.J. she wants a part in the movie, but he refuses. The others agree to allow Lorraine to have a part, as she wants to actually be part of the film and not just recording sound. The scene goes along, but R.J. goes to take a shower where he cries over it.
R.J. begins to drive away to spitefully leave everyone behind, but he stops when he sees Pearl standing in the road. He tries to help her back into the house, but when she attempts to come onto him, he rebuffs her. R.J. continues to try to help, but Pearl stabs him in the neck and then repeatedly stabs him until he is dead, spraying the headlights with blood. Meanwhile, Wayne goes to look for R.J. in the farmhouse and ends up stepping on a nail while barefoot. He then hears something and looks through a hole in the wall, and Pearl impales him through the eye with a pitchfork, killing him.
Lorraine gets up to go look for R.J., while Howard says that Pearl is missing. Lorraine goes into their house to look but ends up getting locked in the cellar by Howard. As she wanders, she turns around to find a man's nude corpse hanging. She screams and begins trying to break out.
Howard gets Jackson to get up and help look for Pearl. They walk by the lake, where Jackson sees a car underwater. He turns around to find Howard saying he knows what Pearl has been up to, and then blasts Jackson in the chest with his shotgun, his corpse falling into the water.
Pearl climbs into bed with Maxine, touching her back and leaving R.J.'s blood on her. Maxine turns around and sees Pearl, causing her to scream. Bobby-Lynne overhears and tries to help Maxine. She sees Pearl running out of the house and follows her to the lake. Bobby-Lynne tries to help Pearl back into the house, but Pearl calls her a whore and then pushes her into the lake, where she is eaten by an alligator.
Lorraine gets an ax and tries to break through the door to escape, but she is caught by Howard, who slams her fingers with his own ax and severs one of them. Maxine hides in the couple's room under their bed when they come in. They talk about the murders, and Howard finally obliges Pearl and has sex with her. Maxine sneaks out and tries to go to the van, only to find the keys missing, but she sees R.J.'s corpse. She grabs Wayne's gun from the glove compartment.
Maxine runs to the cellar to free Lorraine. While she tries to get them out, Lorraine blames Maxine for everything that has happened. Lorraine begins to run out of the house, only to get shot in the face by Howard. As he tries to drag her body inside, Lorraine lets out a dying cough, which startles Howard and causes him to suffer a fatal heart attack. Maxine gets the van keys and aims her gun at Pearl as the TV plays a video of a preacher, with Maxine saying "I will have the life I deserve!" just as the preacher does. Unfortunately, Maxine finds that the gun is unloaded. Pearl fires the shotgun at Maxine and misses, and the recoil is strong enough to blast her out of the house where she breaks her hip. Pearl asks for Maxine's help, and she refuses. Maxine gets into the van as Pearl calls her a whore, and Maxine runs over Pearl's head twice, causing it to burst.
The following day, Sheriff Dentler and the other officers arrive. The video of the preacher keeps playing, and it is revealed that Maxine is his daughter, and he is searching for her. The deputy finds the camera used to film the porno. When he asks Dentler what he thinks is on it, he replies "A goddamn fucked up horror show."
The end credits feature a trailer for an upcoming prequel film called "Pearl".