49 pages 1-hour read

The Intruder

Fiction | Novel | Adult | Published in 2025

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Character Analysis

Content Warning: This section of the guide includes discussion of child abuse, mental illness, graphic violence, substance use, and death.

Elizabeth “Ella” Casey

Casey is the main character of the novel. The chapters titled with her first name are written from her first-person perspective and set in the narrative present. Throughout the majority of the novel, the narrative structure implies that Casey is a separate entity from Ella; in Chapter 53, subtitled “Elizabeth ‘Ella’ Casey,” the narrative reveals that Casey and Ella are in fact the same person. The “Casey” chapters present Casey’s adult perspective, while the “Ella” chapters present her teenage perspective. Casey’s given name was Elizabeth, and she went by Ella throughout her childhood and adolescence. After she killed her mother Desiree, she started using her last name Casey as her first name.


Casey grew up as an only child. She never knew her biological father. Although her mother Desiree was a constant presence in her life, Casey felt unwanted and desperately longed to discover her father’s identity. She was hopeful he would free her from her squalid home life and abusive circumstances with her mother. Desiree was a person who hoarded, a mental illness that compelled her to collect odds and ends, trash, food, and other detritus. As a result, Casey’s house was always filled with debris and paraphernalia. Her living conditions were so bad that she could hardly walk from one side of the house to the other without tripping and could never find proper clothes to wear or food to eat.


Casey’s poor living conditions caused her to retreat from others. She withdrew from everyone at school and tried her best to hide the truth of her mother’s mistreatment. She was bullied often and punished for stealing people’s lunches or getting into fights. Years later, Casey remains reclusive and alienated. The only friend she had was Anton Peterson, who befriended her when she was a teenager. Anton was the only person who seemed to understand Casey. His familiarity with abuse, addiction, and dysfunction made him sympathize with her. He also cared about her as a person and made her feel seen. After Anton was sent to juvenile detention for attacking a classmate who insulted Casey, she was entirely alone. Desperate to free herself, she lit her house on fire and killed her mom in the incident.


In the narrative present, Casey remains fearful, suspicious of others, and prone to aggression. She has been living in a cabin in the woods ever since losing her job for vandalizing a former student’s dad’s car with a baseball bat. Casey still thinks her actions were justified—the man was abusing her student without repercussions—but wishes she hadn’t gotten caught. Her actions caused her to get fired and compelled her deeper into isolation.


Casey takes pity on Eleanor/Nell when she appears at her cabin in the middle of the storm because she identifies with the teenage girl. Eleanor has also been abused and has a penchant for violence as a result. Casey is both afraid of and eager to help Eleanor. When she realizes that Eleanor is about to kill Lee Traynor—who she thinks is her father—Casey intervenes so Eleanor won’t make the same mistake she did. The parallels between her and Eleanor’s experiences help Casey to confront her own childhood trauma in a new way. She finds an unconventional path to healing via her relationship with the young girl.


Casey is an unreliable narrator. Not everything she says is fully true or trustworthy. Her interpretation of events and characters is dubious because she has a history of lashing out at others and is prone to paranoia. She also has a litany of secrets she withholds throughout the majority of the novel. Casey is a largely static character but does show signs of some internal change by the novel’s end. She is still haunted by her traumatic past and tends to act out of fear, anger, and pain. She also resorts to violence yet again when she learns that Jolene Kettering has been abusing Eleanor. At the same time, she begins to soften after befriending Eleanor and Lee.

Eleanor/Nell

Eleanor is one of the novel’s primary characters. She later informs Casey that she goes by the nickname Nell, but Casey primarily refers to her as Eleanor throughout the narrative. Eleanor is the mysterious intruder who appears at Casey’s cabin at the start of the novel. Her character is a literary device (and genre trope) used to incite narrative conflict and mystery. Because Casey does not know who she is or where she came from—Eleanor refuses to answer the majority of her questions—Eleanor remains an enigma throughout much of the novel.


Furthermore, Eleanor poses a threat to Casey’s well-being because everything about her is unsettling or concerning. Her clothes are covered in blood, and her backpack is dripping blood. She is carrying a knife she won’t let go of even while eating. She tells Casey a threatening story wherein she suggests murdering Casey. She takes Casey’s gun and ties Casey up. She also has a notebook filled with sketches of mutilated women on her person. These behaviors make Eleanor a figure of danger and intensify the narrative mood while Casey waits out the storm.


Eleanor’s character subverts the mysterious intruder trope because she is a child. Everything about Eleanor tells Casey that she should fear her. However, she is emaciated, covered in bruises and scars, and scared to sleep alone. These aspects of her character cast her as a scared innocent in need of guidance and care. Casey lets her into her house and agrees to spend time with her because she feels responsible for Eleanor’s safety. She tries gaining her trust so she can help the police find her parents and tends to her injuries while considering how she might place a call to child protective services. Eleanor thus defies the model intruder, as she is a lost, lonely, and hurting child.


Eleanor is a dynamic character because she changes as a result of her relationships with Casey and Lee. She is reluctant to trust Casey throughout the novel but eventually comes to rely on her. She initially sees Lee as the cause of all her pain but later accepts him as her new father figure. With Casey’s and Lee’s help, Eleanor starts to confront the trauma she suffered at her mother Jolene’s hand. Her abusive circumstances closely resemble Casey’s, which makes Casey the ultimate archetypal guide for her. Eleanor ends up staying in the woods with her found family and starting her life over again.

Anton Peterson

Anton Peterson is another of the novel’s primary characters. He features heavily in Ella’s chapters. In the early portions of Ella’s storyline, Anton is an antagonist. He bullies Ella like all of their peers, particularly berating her for looking dirty and smelling bad. Ella sees him as a troublemaker—often encountering him in the principal’s office—but tries her best to ignore his jabs. One day, she saves him from another bully named Devin, and the two become fast friends thereafter.


Anton is a complex character. He initially appears to be a one-dimensional bully with no capacity for sympathy. After Ella saves him from Devin in the park, Anton reveals himself to be sympathetic and capable of change. He apologizes for hurting Ella and doesn’t judge her when she agrees to let him into her house to clean up after the fight. He opens up about his own abusive father and invites her to his house. The two start spending all of their time together and develop a close connection. Anton falls for Ella because she is smart, pretty, and gutsy. She refuses to let other people undermine her and has a soft spot for Anton.


Anton and Ella help one another through the difficulties of Navigating the Effects of Psychological Trauma. Because Ella has come to rely on Anton for emotional stability, she is devastated when he is sent to juvenile detention for attacking their classmate Brittany Carter. Anton was her only friend, and without him, she has no one. The narrative later reveals that the two maintain contact via letter-writing but eventually fall out of touch.


Anton’s character resurfaces in the Epilogue. In yet another plot twist, the narrative reveals that Anton is in fact Eleanor’s biological father. Years after he and Ella were friends, Anton killed his abusive father and was incarcerated. He remains in prison in the narrative present but has requested that his brother Brad (now going by the name Lee Traynor) tell everyone that he’s dead. Lee keeps his promise and does not tell Eleanor her father is alive, nor does he tell Casey that her childhood friend has tasked him with looking out for her. Anton and Ella (now going by the name Casey) don’t get a happy ending, but Anton’s desire to care for Ella withstands the test of time.

Desiree

Desiree is a secondary character. She is Ella’s mom, and thus Casey’s mom, too. She is another of the novel’s antagonists. Throughout Ella’s chapters, Desiree neglects, berates, and abuses her daughter. She is a person who hoards; her mental illness precludes her from maintaining a healthy and orderly home life or caring for Ella. She is also an unhappy character whose dissatisfaction manifests as aggression and violence. She punishes Ella for minor missteps by burning her arms with cigarettes or filling her room with rotten trash. She also has a habit of locking Ella in a closet when she goes out on dates.


Her behavior creates a dangerous environment for her daughter. Ella becomes so entrapped by her mother’s abuse that she ends up killing her in a house fire. In the narrative present, Ella (now going by the name Casey) admits that she regrets her crime because she could have asked for help. At the same time, she still has no tolerance for child abusers, which is why she takes justice into her own hands and kills Jolene on Eleanor’s behalf.

Lee Traynor

Lee Traynor is a secondary character. He is Casey’s only neighbor in the New Hampshire woods. Although he is kind, generous, handsome, and thoughtful, Casey is wary of Lee. She doesn’t trust anyone but is especially suspicious of people who are too kind to her. When she later learns from Rudy that Lee has been asking after her ever since moving in, her paranoia redoubles. Lee is a potential threat who Casey fears will expose her criminal past. Despite her concerns, Casey finds herself falling for Lee over the six months following the storm. In the Epilogue, the narrative reveals that Lee is actually Anton’s younger brother Brad. Lee is thus affirmed as a sympathetic character. He takes care of the people around him, keeps his promises, and makes sacrifices to keep the peace.

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