57 pages • 1-hour read
The Madness of Crowds
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Chapters 31-39Chapter Summaries & Analyses
Content Warning: This section of the guide includes discussion of rape, ableism, suicide, death and illness, child abuse, child sexual abuse, child death, and mental illness.
Chapter 31 Summary
Ewen Cameron was a psychiatrist at McGill University in the mid-20th century. He studied brainwashing by conducting unethical experiments on patients without consent: They came to him seeking help for depression and anxiety. Reine-Marie and Jean-Guy are shocked that Vincent Gilbert could potentially have been involved in these experiments since Gilbert subsequently devoted his professional and personal life to advocating for human dignity. Meanwhile, in Three Pines, Lacoste questions Haniya about her past. Haniya describes being abducted as a child and then being tortured and habitually raped before she escaped. Haniya openly admits that she killed multiple people while escaping, and in revenge.
Chapter 32 Summary
Gamache, Lacoste, Jean-Guy, and Myrna reunite in Three Pines. Lacoste tells them what Haniya shared and explains that she believes Haniya would be willing to kill someone if she believed she was protecting innocent people. Haniya is a serious suspect in the murder of Debbie: She may have been trying to kill Abigail and killed Debbie by accident. Jean-Guy shares his discovery that Vincent Gilbert worked with Ewen Cameron, while Gamache confirms that Simon was his father’s accomplice and remains a suspect in Debbie’s murder.
Chapter 33 Summary
Reine-Marie looks through Enid’s final box. She realizes that Enid received treatment from Dr. Ewen Cameron after seeking help for post-partum depression and rushes to tell Gamache, who has independently come to the same conclusion. The same letter that confirmed Enid received treatment from Dr. Cameron was also signed by Vincent Gilbert, proving that Gilbert was aware of the cruel experiments. Meanwhile, Jean-Guy has requested additional information about the deaths of Abigail’s deceased family members—her mother, father, and younger sister Maria. He has confirmed that Maria died by choking on a sandwich. Lacoste also tells Edouard Tardif that Simon has been arrested and charged with accessory to attempted murder; Tardif is filled with regret about involving his son.
Chapter 34 Summary
Jean-Guy and Gamache confront Vincent Gilbert with the document, and Gilbert admits that he knew about Cameron’s experiments. Gilbert initially took the job to pay his bills as a young medical student but stayed on even after he knew that Cameron was experimenting on both humans and animals. Gilbert realizes that Enid obsessively drew monkeys for the rest of her life because she was kept in a room next to the monkey enclosure, spending hours listening to their screams. Gilbert also admits that when he and Abigail argued at the party, he feared that she knew about his history with Cameron; this fear would have given him an incentive to kill Abigail, and he admits that he considered it. He’s not sure whether Colette knew how far he was willing to go to stop Abigail. However, Vincent insists that he is not the killer: “[S]omeone got there first. Except they messed it up. Killed the wrong person” (293). Gamache is increasingly alarmed that Colette could be a threat to Abigail; he takes Vincent Gilbert into custody and sends a police presence to Colette’s home.
Chapter 35 Summary
Gamache, Jean-Guy, and Vincent Gilbert arrive at Colette’s home. Gamache accuses Colette of having a role in “the conspiracy […] to stop Professor Robinson, by killing her if necessary” (295). Abigail is deeply confused because Colette is so supportive of her. Abigail reveals that she came to Quebec in hopes of persuading Vincent Gilbert to endorse her arguments, and she believed that Colette (who was friends with Gilbert) would help her. Colette admits that she was deceiving Abigail and planned to work with Gilbert to show Abigail that she was wrong. Gilbert also explains that he gradually came to believe that killing Abigail would be morally justifiable. Abigail is angry to learn that Colette and Gilbert were conspiring against her, and she accuses Gilbert of killing Debbie.
Gamache coaxes Abigail into admitting that she knew about Gilbert’s history of working with Cameron. Abigail hints that she would have been willing to use this information to blackmail Gilbert into endorsing her arguments, if necessary. However, while this conversation is unfolding, Gamache receives additional information from Lacoste and Jean-Guy: Abigail’s mother died by suicide when Abigail was a child, after “receiving treatment” from Dr. Cameron. Abigail subsequently learned that Vincent Gilbert had worked alongside Cameron. She admits that she lied about wanting Gilbert to endorse her theories: She actually wanted revenge.
Chapter 36 Summary
Gamache and his team take Abigail out of Colette’s home and put her under partial custody at the inn, where Vincent Gilbert is held on another floor. Gamache, Lacoste, and Jean-Guy discuss possibilities based on the new information that has been unearthed: Debbie (who also knew about Gilbert’s history with Cameron) may have confronted Vincent with this information at the party, and he could have panicked and killed her. Alternately, Debbie could have confided in Colette about the plan for Abigail to blackmail Gilbert, and Colette could have responded by killing her. Jean-Guy even suspects that the death of Abigail’s father might have been suicide, driven by grief after the loss of his wife. Abigail might have sought to avenge both of her parents.
Chapter 37 Summary
Gamache, Jean-Guy, and Isabelle meet with a coroner, with whom Gamache has shared reports about the deaths of Abigail’s family members. She confirms that the death of Abigail’s mother was almost certainly suicide; the death of Abigail’s father is more ambiguous, and the coroner concedes it could have been natural causes. However, she shares her unofficial theory: She thinks that Maria’s death was not accidental: “I think her father killed her, then later took his own life” (312). The coroner speculates that Abigail’s father was crushed by grief after his wife’s death. Overwhelmed by caring for a child with a disability, he suffocated Maria, later making the death look accidental. Meanwhile, Reine-Marie prepares to meet with Enid’s children and tell them that their mother suffered at the hands of Ewen Cameron. She invites Haniya to come with her.
Chapter 38 Summary
Isabelle watches via video call as local police officers search Debbie Schneider’s home in British Columbia. In the nightstand, they find an old photo depicting Debbie, Abigail, Maria, and Maria and Abigail’s father, Paul Robinson. Isabelle wonders why Debbie would keep the photo close by, yet hidden. Meanwhile, Gamache and Jean-Guy ponder why Debbie ended up dead when Abigail was widely disliked.
Chapter 39 Summary
Reine-Marie and Haniya meet with James and Susan, Enid’s grown children. Reine-Marie decides not to tell them about the horrific experiences their mother endured. Jean-Guy shares with Gamache that he no longer believes Paul killed Maria. They wonder if Debbie or Abigail could have killed Maria, or if focusing on Maria’s death is merely a distraction from Debbie’s murder. They begin to consider the possibility that if Debbie murdered Abigail’s sister and Abigail eventually found out, she would have had a motive to kill her best friend.
Chapters 30-39 Analysis
In this section, the murder investigation progresses, and the case becomes more complicated as the pool of suspects grows. Gamache himself feels confused as to whether emerging information is relevant or simply a distraction. The information that Colette has secretly been colluding with Vincent Gilbert to dissuade Abigail from her theory is a significant plot twist: Even Abigail is astonished when Colette admits that “we planned to talk you out of it” (296). This information positions Colette as a potential suspect, since, if she vehemently disagrees with Abigail’s theories, she has an incentive to stop her from spreading them. It also reveals that virtually all characters in the novel can keep secrets, and no one’s motives are entirely clear.
Colette’s duplicity also complicates her moral positioning. She is not an outspoken supporter of Abigail’s ideas, but she is not a public opponent until her covert plan with Gilbert is revealed. This places her in the ethically murky space of performative neutrality. Penny uses this dynamic to show how even silence, or delayed opposition, can be dangerous when the stakes involve real lives. Colette’s shift from passive bystander to covert resistor mirrors the inner turmoil of many characters who are unsure how or whether to intervene in a crisis fueled by ideology. This ambiguity powerfully reflects the theme of Bias and Emotion Impacting Decisions, as characters like Colette struggle to reconcile personal loyalty with moral action.
While Vincent Gilbert remains positioned as a suspect, his motives shift: At first, it seems he would most likely have killed Debbie while mistaking her for Abigail and attempting to protect the innocent people from her policies on “mercy-killing.” However, it becomes increasingly possible and even probable that, if Vincent is the killer, he operated from more selfish motives of protecting his own reputation. The growing ambivalence surrounding his character and what he might have done further develops the theme of Bias and Emotion Impacting Decisions.
This shift is underscored when Gilbert admits, “someone got there first. Except they messed it up. Killed the wrong person” (293). His use of clinical detachment to describe a murder reveals how rationalization functions as a coping mechanism for moral failure. Gilbert’s transformation mirrors the journey of many public figures in the novel who begin with principle and are undone by fear. Penny raises the uncomfortable question of whether even righteous people, when faced with exposure, can be pushed to acts of self-preservation, highlighting selective ethics as they relate to personal reputation.
This section includes significant development of the theme of Parental Desire to Protect Children as it becomes evident that Maria was deliberately killed, and that her own father is implicated in either the crime or the cover-up. This additional element to the murder investigation is extremely distressing to both Gamache and Jean-Guy. Since both men are devoted fathers, they find it horrifying to contemplate that a man could harm his own daughter. Jean-Guy reflects that “he would die before he’d let anything happen to either of his children. In fact, he would kill” (314). This moment reflects the theme of Bias and Emotion Impacting Decisions since Gamache increasingly considers that the suspect is “[…] someone whose love was so great it had moved them to murder” (343).
Penny continues to blur the line between protection and possession. Paul Robinson’s possible act of filicide—whether done to end suffering or to ease his own burden—calls into question the nature of parental love, particularly if it is rooted in fear, shame, or resentment. Gamache’s and Jean-Guy’s horror at this possibility reveals how they project their own understanding of fatherhood onto the people they investigate, exposing how emotion shapes their logic even as they try to be impartial investigators. In this way, both Parental Desire to Protect Children and Bias and Emotion Impacting Decisions become intertwined, challenging the reader to consider whether deep love can sometimes become the seed of violence.
The motif of documents and mementoes emerges strongly in this section because the clue to the central mystery seems to lie in the past. Unlike many other murder mysteries, Gamache does not rely on any sophisticated technology to solve the crime. Instead, he makes use of his keen awareness of human psychology to draw connections and unveil motivations. Documents such as old photos, agendas, and letters shed light on experiences from decades earlier in the cases of Enid Horton and Paul Robinson. These documents are important because the true motive for Debbie’s murder stretches back decades, and thus the truth can only be found with access to the past. Significantly, in the case of Enid Horton, Reine-Marie opts not to share the truth with Enid’s children, telling them instead, “your mother loved you. That’s what’s in the box” (347). This decision foreshadows the subsequent revelation that Paul was also trying to protect his surviving daughter by focusing on love and concealing her secret.
Archival evidence also becomes a metaphor for repressed memory, both personal and collective. Just as Reine-Marie sifts through boxes of Enid’s life, the investigation itself becomes an excavation of psychological history. The monkey scratched into Enid’s wall, the old photograph in Debbie’s drawer, the childhood nickname “Abby Maria”—each functions as a breadcrumb leading back to a deeper trauma. These fragments show how seemingly trivial details can serve as the repository of truth, especially when official narratives like medical records or autopsy reports are ambiguous or misleading.
This section reveals how deeply the novel is concerned not just with who committed a murder, but with how people carry grief and guilt through generations. The themes of Parental Desire to Protect Children and Bias and Emotion Impacting Decisions operate in tandem here, as love becomes both the motive for concealment and the lens through which evidence is interpreted. As the past grows heavier with each revelation, it becomes clear that the murder of Debbie Schneider cannot be solved without confronting the emotional inheritance of everyone involved.
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