Three girls living at the Murder House when it's a boarding room are preparing to leave for the Hollywood Bowl to hear Jim Morrison and the Doors perform. They jokingly invite their roommate, Maria, to come along with them. She's studying for a medical final and chooses to stay, along with Gladys, a girl working as a nurse. Once they leave, there's a knock on the door. Maria answers and finds a man, R. Johnson, at the door, His head is bleeding from an apparent injury and he asks to come in. Maria brings him in and treats his wound, and he comments on the cross that she's wearing. When he asks her of he thinks Jesus can save her, Maria says that they're all saved. When Maria realizes that the blood is fake and Johnson doesn't have an injury, he knocks her out with an ashtray and then attacks Gladys.
When Maria wakes up, Johnson tells her to remove her clothes and put on a nurse's uniform. She hesitates, saying that she's a version, but Johnson orders her to strip. Once she does, Johnson ties her up and puts her on her stomach on the couch. She prays to God to deliver her soul when she dies, and then looks up and discovers that Johnson has seemingly vanished. As she wonders if he's left, Johnson stabs her in the back repeatedly.
Tate comes to the house for another session with Ben. Ben ignores his cell phone as it rings and Tate asks if he's thinking about sex. The teenager talks about how he masturbates while thinking about Violet and Ben ignores the attempt to rile him. Tate complains that Ben isn't helping him conquer his visions and asks about Ben's affair, and Ben says that their session is over. Once Tate leaves, Ben receives another call and answers it. The woman calling says that she's pregnant.
Violet meets Leah at an empty swimming pool converted to a skate park. Leah is smoking and wearing a hate and coat, and insists that they both saw the creature in the basement. Violet says that it was just Tate trying to freak them out, but Leah reveals that her hair is turning white from fear of what she saw. Leah insists that she saw the Devil in the Murder House and looked into its eyes.
That night, Violet sleeps in her bed while Tate watches her. The security alarm goes off, waking up the family, and Ben runs downstairs with a baseball bat. He hears someone in the basement and investigates, and finds Adelaide playing with a ball. As Ben leads her out, they're unaware that something behind them rolls the ball across the floor.
Once Ben sends Adelaide home, he talks to his wife and refers to Adelaide as a freak. Offended, she snaps at him and then admits that she's on edge because she hasn't shown any signs of pregnancy yet. Ben tries to assure her that it's normal for her to have concerns, but Vivien tells him to stop analyzing her. He tries to reassure her, insisting that the baby is their salvation.
The next day, Ben meets with another patient, an actress named Bianca. She talks about her dream where she tries to climb out of an envelope through the door and is cut in half. Ben tries to analyze it but Bianca prefers to talk about the Murder House, explaining that it's on the Hollywood tour and that's why she became Ben's patient. Surprised, Ben focuses on Bianca's dream and suggests that she feels there is something in her that is shutdown. Afterward, Ben goes to the kitchen and calls Tate's mother and says that he can't treat her son anymore. Bianca comes through and apologizes, saying that she got turned around, and Ben guides her to the front door.
Constance is at home making cupcakes and talking to Adelaide. Adelaide wonders why she doesn't look like other girls and Constance says that she has special gifts instead. However, she can't think of any. Constance then puts ipecac in the cupcake dough and has her daughter spit in it.
Ben is jogging and stops in a tunnel to cry when he remembers his affair. Larry finds him and warns Ben that the house knows what is tearing him up and will use it against him. Ben insists that his problems have nothing to do with the house, and then admits that his mistress, Hayden, called from Boston. Larry tells him that to save his family, Ben will have to lie. Ben goes home and tells Vivien that the parents of one of his former patients, Ginny, wants him to come back to Boston and help her. Vivien accepts his lie and says that he's a good man.
The next day, Constance comes to the Harmon home and shows her two cupcakes that she's made for Violet. She immediately smells Vivien's pheromones and realizes that she's pregnant, and insists on giving the cupcakes to Violet personally. When she learns that Violet isn't home, Constance starts to leave but Vivien asks her to stay for coffee and asks if she can smell anything else about her child. As they talk, Vivien cuts one of the cupcakes in half and offers one half to Constance. She asks what the former actress would do if she had known Adelaide was developmentally challenged before the girl was born, and Constance admits that she would have still kept her. She talks about how she has three other children, and two of them also physical maladies. The third, a boy, is physically perfect but Constance admits that he has mental problems.
As the two women talk, Ben comes through the kitchen as he departs for Boston and notices the cupcake. Constance pulls it away and then orders Moira to clean it up as the housekeeper comes in. The ex-actress explains that she and Moira go way back and that Moira used to work for her. Constance then says that it's heartbreaking when the promise of a child is broken and leaves. As they talk, Ben sees the Young Moira as she takes his bag to the car. Once they're alone, Ben hugs Vivien and says that he wishes she could come with him.
That night, Vivien comes to see Violet in her room and offers her Constance's cupcake and a girl's night. Violet insists that she has homework and then complains that Vivien didn't tell her that she was pregnant. She warns her mother of the statistics with a pregnant woman over 40 and her mother asks if she wants to talk about it. As Vivien leaves, Violet warns that having a baby won't keep her and Ben together and that Vivien is weak. Once her mother leaves, Violet sets the cupcake out in the hallway.
Ben is meeting with Hayden at her apartment when Vivien tries to call him. He ignores it and talks to Hayden, who offers a glass of wine and thanks him for his support. Ben promises that he'll be there for her through her abortion and then offers her a toast to her grace and maturity. However, when Hadley goes to the door for a pizza delivery, she sees Ben as he gets another call from Vivien. She breaks into tears, saying that just wanted Ben to love her, and he turns off his phone and puts it away.
Vivien is watching a horror movie when the front door bell rings. She looks out through the peephole and sees a young woman with a bleeding head wound. The woman, Fiona, asks Vivien to help her but won't provide any details and asks Vivien to open the door because someone is after her. Realizing something is going on, Vivien goes to call 911 but discovers that her phone is missing. She goes back to the door and discovers that Fiona is gone. Violet comes downstairs and Vivien tells her to get her phone and dial 911 as the doorbell rings again. As Violet looks for her phone, a masked figure comes up behind her. Vivien goes to the front door and yells that the police are on their way, and another masked figure grabs her.
The three masked intruders tie up violet and Vivien. Fiona removes her mask and tells the other two to do so as well. One of them is Bianca, another is their friend Travis. They explain that they're there to recreate Johnson's murder of Gladys and Maria in 1968, when he drowned Gladys in the tub and then stabbed Maria to death. Fiona tells them to put on nurse's uniforms and unties Violet. She fights back and runs through the house, and Tate grabs her and yanks her into the pantry. He tells Violet to get them to the pantry and then slips away as Fiona and Bianca find her and haul her away.
Travis tells Vivien that he wants to kill her, unaware that Adelaide is in the house behind him. Vivien loudly tells him that someone will see him and get help, and when he turns around, Adelaide has slipped away.
Fiona fills up the tub and watches as Violet puts on the nurse's uniform. Bianca finds the cupcake and eats it, and then starts having stomach pains. Fiona tells her to go to a different bathroom so she doesn't spoil the staging area, and then orders Violet into the tub. Violet says that it's not the original tub, and they have the original tub stored in the basement after they remodeled.
Constance is in her bedroom with a young shirtless man, stroking his chest. He tells her that she's beautiful and Constance asks him to dance with her. They begin to kiss but Adelaide knocks on the door. She tells her mother that there's a bad man next door but Constance figures that Adelaide is talking about Ben and says there's nothing they can do about it. When Adelaide persists, Constance locks her in the bad girl closet, which is filled with mirrors. Adelaide screams in terror at the sight of her reflections, and Constance goes back to her bedroom.
Bianca throws up into a wastebasket and then goes back to the bathroom. Tate attacks her with an axe and hits her in the stomach. She staggers away, leaving blood on the walls.
Travis puts a cross on a necklace around Vivien's neck, and then cuts her free and tells her to put on the nurse's uniform. She throws the dress in his face and tries to run. Travis tackles her and she manages to grab the ashtray and hit him in the head. Once he's down, Vivien beats him in the head several more times.
Fiona takes Violet downstairs into the backroom. The lights go out and Tate calls to her. He's standing next to the tub, filled with water. Gladys is in it and rises out of the water.
Vivien finds Violet and they run out of the house. Constance sees them go by, yelling for help.
Travis wakes up and sees someone in a nurse's uniform walking by. He figures that it's Violet and follows her into the basement. He finds Fiona, her throat cut, and Gladys and Maria standing by the tub.
The next morning, Ben accompanies Hayden to the hospital. She insists that it's the right thing for both of them, and Ben says that he wishes he could fix it. When Hayden is called into the doctor's office, Ben tells her that he'll be there when she's done. His phone rings and he realizes that he's missed 13 calls from Vivien.
Constance goes to the murder house basement and finds Tate and Moira there. Moira says that it was “their” work, and Tate warns that they have to get rid of the bodies so Ben will keep treating him. Moira says to get the bleach and the axe.
When Ben returns, detectives Webb and Collier question Ben and explain that they found Bianca's corpse six blocks away, cut in half. She was part of a club that recreates famous murders, and they plan to keep looking for her accomplices. Violet comes in and Ben asks her about Tate, who helped her escape. He wonders why Tate was there and Violet says that she didn't know, but Tate was there and Ben wasn't. As she goes, Violet tells her mother that she was really brave. Once she leaves, Ben apologizes for being gone and Vivien says that they're selling the house.