52 pages 1-hour read

A Stranger in the House

Fiction | Novel | Adult | Published in 2017

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Chapters 10-21Chapter Summaries & Analyses

Content Warning: This section of the guide includes discussion of graphic scenes of death and injury, domestic abuse, and mental illness.

Chapter 10 Summary

Karen walks into the house and immediately notices an empty water glass next to the kitchen sink. She is certain it was not there when she left. She picks up the glass, but then she gets dizzy and drops it. She calls Brigid and asks her to come over right away. She tells Brigid she is sure the glass was not there when they left the house. Brigid calls Tom, who rushes home.


Tom wonders if Karen is not misremembering that there was not a glass there. He cannot find any other evidence that someone else was in the house. He wonders if she is having memory problems because of the accident. Karen reluctantly responds “maybe.” Karen thanks Brigid for her support and Brigid leaves.

Chapter 11 Summary

Detective Rasbach enters the abandoned restaurant where the dead man’s corpse has been found. Someone anonymously reported it. It smells very bad as the body has been rotting in the summer heat for several days. He notes the man was shot three times in the face and chest. He sees the man has dark hair and a nice suit and thinks the man does not belong in that neighborhood. The man has no identification on him, and his personal effects are missing.


The police find no other clues in the area except “a pair of pink rubber gloves with a floral print near the elbows” (66) in a parking lot nearby.


The next morning, the medical examiner tells Detective Rasbach the man was shot at close range with a .38 caliber handgun about four days ago. Rasbach and his team look at arrest records and learn that a Honda Civic hit a utility pole near the scene of the crime on August 13th at 8:45 p.m.

Chapter 12 Summary

Detective Rasbach meets with Officers Fleming and Kirton about the accident. They tell him that Karen Krupp, the driver, has no memory of the night in question. He wants to see the Civic. He thinks the accident and the murder are connected. Things have been tense between Tom and Karen since she returned home. Tom realizes that he knows nothing about his wife’s past.


The crime technician confirms that the tire tread on the rubber gloves approximately match the tires of the Civic, but they cannot be completely certain. They are going to try and get DNA from the inside of the gloves.


Detective Rasbach and his partner Detective Jennings go to the Krupp home to interview Karen.

Chapter 13 Summary

Karen is nervous, but she agrees to speak with Detectives Rasbach and Jennings. They tell her they are investigating a murder. She tells them she remembers nothing about the night in question. They ask if she is missing a pair of rubber gloves. She lies and denies owning such a pair of gloves. They press her, telling her that the tread marks on the gloves exactly match those of her Honda Civic. At that moment, Tom arrives. He is shocked to learn they are investigating a murder. Like Karen, he lies and says they are not missing any rubber gloves.


The detectives show them pictures of the murdered man. Karen says she does not recognize him. The detectives leave.

Chapter 14 Summary

Detective Rasbach thinks Karen is hiding something. He did not believe their lie about not owning a pair of rubber gloves. He decides to look into their phone records to learn more about them.


Meanwhile, Tom is badly shaken by the interview. He is angry that Karen lied to the detectives about the gloves. They argue. Karen asks if he really thinks she is capable of murder. Tom evades answering. He tells her that he loves her but that he is scared.


That evening, Karen sees the detectives return to the neighborhood. They canvass the nearby houses, talking to the neighbors about what they saw the night of the incident.

Chapter 15 Summary

Brigid is at home knitting, her favorite pastime. She has spent more time on it since she quit her job to pursue fertility treatments that ultimately did not work. Detectives Rasbach and Jennings appear at the door. They ask her about the night of August 13th. Brigid says she was not at home that evening and that she believes her husband, Bob, was also not at home.


That night, Tom lies awake wondering, “[W]hat will the police find?” (93).

Chapter 16 Summary

The next morning, Karen meets with lawyer Jack Calvin alone. She tells him that the police are investigating her for murder. She tells Calvin that she and Tom lied about the missing rubber gloves. Calvin tells her not to speak with the police again and that if they contact her she should tell them to contact him instead. He thinks they do not have enough evidence to charge her yet.

Chapter 17 Summary

Detective Rasbach runs a background check on Karen. He sees she has no criminal record. He then researches her maiden name, Karen Fairfield from Milwaukee, Wisconsin. He finds no records that such a person exists. He thinks, “Tom Krupp’s wife isn’t who she says she is” (100). Detective Jennings tells Rasbach that there was a call from an untraceable burner phone to the Krupp residence at 8:17 p.m. on August 13th, the night of the accident. They had learned from neighborhood witnesses that Karen left her house in a hurry shortly after she received that call. They wonder if the call was for Karen or Tom.


Leaving the lawyer’s office, Karen fights the instinct to run because “she knows how to disappear” (101), but she doesn’t want to because she loves Tom.


Brigid calls Tom at work. She tells him that, on the day of the accident, a man matching the description of the murder victim had been looking around the Krupp residence. The man had told Brigid he was an “old friend” of Karen’s “from another life” (102). Brigid tells Tom she once saw a TV show about how people hiding from their pasts can “take on a new identity” (102). They hang up. Tom is shaken by the call.

Chapter 18 Summary

Tom arrives home from work angry; he feels Karen has been hiding things from him.


Brigid sits at home alone, knitting. She reflects on how guarded Karen has always been with her, even though they are best friends. She decides to bring the Krupps some brownies.

Chapter 19 Summary

Detectives Rasbach and Jennings return to the Krupp residence. They press Karen on whether she remembers anything from the accident. She continues to insist she does not remember anything. They ask her about the phone call she received at 8:17 p.m. She says she does not remember. They suggest the call was for Tom.


Brigid arrives at the Krupp residence with her brownies. She overhears them talking to the detectives. She decides to leave the brownies by the back door for them.

Chapter 20 Summary

Tom insists to the detectives he has nothing to hide. The detectives state they learned that Tom left work at 8:20 p.m., but he did not return home until 9:20 p.m. He says he was “driving around” for an hour and that he stopped off at a park for a short while. They are skeptical and leave. Karen wonders what Tom was really doing for that hour because she knows he does not like to drive. She asks him about it. He storms out. She sees the brownies Brigid left and realizes Brigid overheard their conversation.


Tom goes to the bar. He thinks about how he once had an affair with Brigid. He was supposed to meet her at the park that evening, but she never showed up. He doesn’t know why Brigid wanted to see him that evening. He feels guilty for not having told Karen about his affair with Brigid.


Tom returns home. He suggests Karen see a hypnotist to try and recover her memories. She does not think it will help and refuses.

Chapter 21 Summary

Karen goes for a walk. Brigid sees Karen has left and goes to talk to Tom alone. She tells Tom that the reason she had asked to meet with him the night of the accident is because she had wanted to tell him about the strange man poking around the Krupp house. She didn’t show up because her sister had called and she had not been able to get away. Tom says he doesn’t “want to talk about it” (123).


Tom feels relieved when Brigid leaves. He feels tense around her since their affair, and he resents her close friendship with Karen. He wonders why Karen won’t try harder to remember what happened that night. He pours himself a whiskey and waits for Karen to return home.

Chapters 10-21 Analysis

In Chapter 10, the most literal meaning of the title A Stranger in the House becomes clear. Karen is concerned because she has found evidence that someone has been entering the house and going through their things, as evidenced by the water glass left on the side of the sink. This is one possible meaning of the “stranger in the house” to which the title refers. However, the so-called stranger is later revealed to be Brigid, the person whom Karen calls immediately after finding evidence of this “stranger.” Brigid is not a stranger, but rather one of Karen’s closest friends and Tom’s former lover.


The reveal that Brigid is the stalker suggests another meaning to the title A Stranger in the House. It implies that Karen is in fact the “stranger.” As the investigation into the car crash continues, Tom reflects that Karen is not the woman he thought he knew. Indeed, “he realizes he doesn’t really know that much about his own wife” (73). This relates to the theme of The Impact of Secrets on Relationships. Tom is forced to reckon with the possibility that Karen is hiding secrets from him and that, as a result of those secrets, she is essentially a “stranger” to him. He is likewise haunted by the secret he is keeping from Karen about his affair with Brigid. The shame of this secret drives him to self-destructive behavior, such as isolating himself from Karen and drinking alcohol alone.


The novel plays on common expectations about works in the domestic thriller genre to create red herrings, or misleading clues. A key example of this is found in Chapter 10. After Karen finds the water glass, she insists to Tom it was not there before they left the house. Instead of believing her, he questions her memory: “Are you sure it wasn’t there before? It could have been” (61). He then reassures her that no one was in the house and suggests she is having “short-term memory” problems as a result of her accident (62).


Tom’s dismissal creates the impression that Tom is potentially “gaslighting” Karen. The term “gaslighting” refers to the way an abuser will lie to their victim about what they are experiencing to discredit their understanding and create uncertainty in their sense of reality. The term is a reference to the 1940 psychological drama Gas Light wherein a wife grows increasingly concerned about the house gaslights dimming; her conniving husband attempts to convince her that she is simply seeing things, even though he knows the gaslights are dim when he is using the lights in the attic while he steals her valuables. Husbands or boyfriends “gaslighting” their female partners is therefore a common trope of this genre. The narrative implies that this may be what is going on in this scene. However, it is a red herring because it is later revealed that Tom was simply attempting to calm his injured wife and he had no idea Brigid was breaking into the house.


This section of the novel introduces the theme of The Reinvention of Identity. Fittingly enough, it is Brigid, Karen’s rival and foil, who raises the possibility of Karen’s identity being false. She calls Tom to suggest that perhaps Karen is “running from [her] past” by “disappear[ing] and tak[ing] on a new identity” (103). Tom is discomfited by the idea, but he is forced to consider that his wife may be “using a fake identity” (103). Brigid herself later attempts to reinvent herself by adopting a new identity, that of Karen Krupp. Thus, it is appropriate Brigid is the character who would suggest Karen ran from her previous life and created a new one more closely aligned with Karen’s twisted “American dream” alluded to in Chapter 1.

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