Analysis of ‘Split’ Movie
The psychological thriller film “Split,” directed by M. Night Shyamalan and released in 2017, featuring James McAvoy, remains my favorite entry in the psychological thriller genre to date. The narrative revolves around Kevin Wendell Crumb (played by McAvoy), a man suffering from Dissociative Identity Disorder (DID), who possesses 23 distinct personalities. A 24th persona, known as “The Beast,” emerges later in the story. This film explores themes of trauma, survival, and the extraordinary capabilities of the human mind. Its impact lies in the seamless blend of psychological tension, exceptional acting, and profound thematic exploration, resulting in a gripping and thought-provoking viewing experience. Furthermore, the film intricately examines Kevin’s DID as a response to trauma, stemming from childhood abuse, illustrating how the mind can fragment as a means of self-protection.
The portrayal of Kevin’s “Beast” persona introduces an exaggerated element of superhuman evolution, merging psychological horror with comic-book mythology. For this paper, I will analyze Kevin’s character, discuss the nuances of his disorder, evaluate the accuracy of its depiction with Dr. Carson’s course material, and explore the potential etiology of his issues through the lens of environmental and biological factors, along with proposed treatment options.
Plot Synopsis
The film revolves around a man with dissociative identity disorder who kidnaps and holds three teenage girls captive in a hidden underground facility. The girls, Casey Cooke (Anya Taylor-Joy), Claire, and Marcia, are abducted from a parking lot by a mysterious man named Kevin Wendell Crumb, played by James McAvoy. They wake up confined in a windowless underground room, feeling disoriented and terrified. Their captor displays erratic behavior, shifting between various personas: Dennis, a controlling man with obsessive-compulsive tendencies; Patricia, a stern matronly figure; and Hedwig, a playful 9-year-old boy.
As the girls start to piece together that Kevin has dissociative identity disorder (DID), they try to use his different alters to help them escape. While Claire and Marcia panic, Casey remains calm and observant, carefully analyzing Kevin’s behavior. Flashbacks reveal her traumatic childhood, marked by abuse from her uncle, and this background allows her to understand predators better. She forms a bond with Hedwig, manipulating him by treating him like a child.
Kevin’s psychiatrist, Dr. Karen Fletcher, suspects that a menacing new alter is surfacing. She theorizes that DID might unlock hidden physical abilities, altering body chemistry and strength. When she discovers that Kevin has kidnapped the girls, she rushes to intervene, only to meet a tragic end at the hands of “The Beast”.
Ultimately, Kevin’s most feared alter, “The Beast,” takes over, transforming into a superhuman and animalistic entity that believes those who have suffered abuse are “the blessed.” The Beast brutally kills Claire and Marcia but spares Casey upon noticing her scars, which signify her status as a fellow survivor. She was rescued the next day by the police.
The movie dives deep into themes of trauma and survival, showcasing Kevin’s dissociative identity disorder as a response to his childhood abuse and illustrating how the mind splits to protect itself. Casey’s parallel story highlights her survival instincts, honed through her own experiences, making her the only one capable of outsmarting Kevin and adding emotional depth to the narrative. The film suggests that while trauma can create monsters, it can also birth survivors.
Character Description of the Person with Disorder
Kevin exhibits 24 alter-personalities (including ‘The Beast’, which was formed later), marking the first indication of his struggle with Dissociative Identity Disorder (DID). Kevin’s psychiatrist diagnoses him at the beginning of the movie, affirming this diagnosis with several symptoms. For example, Kevin displays clear dissociation between his alters, each of whom is aware of the others. When one alter takes control, the others are unaware of the actions performed. There are also clear differences in their mannerisms, speaking styles, and capabilities. While the primary focus is on DID, the film also specifically addresses one of Kevin’s personalities, “Dennis,” who exhibits symptoms of a comorbid obsessive-compulsive disorder (OCD).
APA Diagnostic Criteria for Dissociative Identity Disorder
According to the DSM-5, DID has the following diagnosis: Disruption of identity is characterized by two or more distinct personality states (known as “alters”); here, the character Kevin has 24 distinct alters; there are recurrent gaps in memory (amnesia) for everyday events, important personal information, or traumatic experiences (Kevin experiences blackouts when other alters take over; he cannot remember abducting the girls while he is in his Barry alter); These symptoms cause clinically significant distress or impairment in functioning (In the film, Kevin’s alters engage in harmful behaviors such as kidnapping and violence, indicating severe impairment); Furthermore, the disturbance is not part of a broadly accepted cultural or religious practice (Kevin’s condition is not culturally sanctioned); Lastly, symptoms are not attributable to substance use or another medical condition; there is no indication of substance use in the movie, causing Kevin’s alters (APA, 2022).
Different Personalities as Portrayed
Some notable alters include Dennis, who serves as the primary “protector” of the system and functions as an enforcer. He exhibits obsessive-compulsive tendencies, particularly a fixation on cleanliness and order, and displays violent, dominant, and controlling behavior.
Patricia is a maternal and authoritarian figure who communicates in a calm, sophisticated manner. She acts as a gatekeeper for the other alters. Hedwig is a vulnerable and childlike alter, presenting as a 9-year-old boy. Energetic and naive, he is easily manipulated, often used by Casey to gain an advantage. Hedwig has a fondness for songs and dancing.
Barry is the extroverted facade that Kevin uses to interact with the outside world. He is fashion-conscious and outgoing, initially engaging with Dr. Fletcher. The Beast is a primal, superhuman alter awakened by trauma. He possesses extraordinary strength, agility, and pain resistance, believing he represents the next stage of human evolution. The Beast only targets the “unworthy,” sparing those who have experienced suffering, such as Casey.
Deviation from DSM-5 Realism
Split takes creative liberties with DID, particularly in depicting alters with supernatural traits. While it captures some DSM-5 criteria, such as identity fragmentation and amnesia, it exaggerates others for dramatic effect, which can contribute to stigma surrounding the disorder.
For instance, the extraordinary abilities attributed to “The Beast” do not correspond to reality, as Dissociative Identity Disorder (DID) does not endow individuals with superhuman strength or the capacity for physical transformation (Carson, 2025). Individuals with DID are much more likely to be victims of violence rather than aggressors (Dorahy et al., 2014).
When aggression does occur, it is often directed inward, manifesting as self-harm or suicide attempts, typically stemming from severe childhood trauma such as abuse or neglect (Dorahy et al., 2014).
Treatment for DID
The treatment approach proposed by Brand et al. in 2014 emphasizes a phase-oriented strategy, comprising three stages (as given below), that is commonly recommended for Dissociative Identity Disorder (DID). In Stage 1, the focus is on stabilization, safety, and fostering communication between differing “self-states.” Patients are taught skills for emotion regulation and impulse control. Stage 2 involves the processing and integration of traumatic memories through therapies such as exposure therapy. In Stage 3, the treatment addresses challenges in daily living, the formation of healthy relationships, and engaging in meaningful activities, all while working towards identity integration and rehabilitation (Brand et al., 2014).
As individuals begin to recognize their shared history, they start to amalgamate their memories and personality traits, and in some instances, complete integration is achievable; however, in other cases, individuals may only partially integrate but will still experience enhanced functionality as a whole (Carson, 2025).
Additional therapies such as Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) can aid in integrating dissociated identities by processing trauma (Brand et al., 2013). Eye Movement Desensitization and Reprocessing (EMDR) can also be beneficial for treating DID, particularly after initial stabilization (Phase 1) (Fine & Berkowitz, 2001). Additionally, Dialectical Behavior Therapy (DBT), which incorporates mindfulness techniques, can support emotion regulation, and DBT skills training has been shown to reduce self-harm in individuals with DID (Brand et al., 2009).
One of Kevin’s alters, “Dennis,” has a comorbid diagnosis of Obsessive-Compulsive Disorder (OCD), which can be treated alongside Dissociative Identity Disorder (DID) using Exposure and Response Prevention (ERP) in conjunction with Cognitive Behavioral Therapy (CBT) (Dorahy, M. J., et al., 2014). However, it is essential to modify the ERP approach to include internal communication, such as journaling between the alters, to enhance safety (Dorahy, M. J., et al., 2014).
In contrast to this established treatment model, the portrayal of DID treatment in the film “Split” is not an accurate representation. Specifically, the psychiatrist in the movie fails to engage in the integration of the alters as recommended by the above-mentioned treatment model by Brand et al. in 2014. Instead, she encourages the alters to “take turns” without a structured integration process that emphasizes collaboration, stabilization, and integration (Brand et al., 2014).
Furthermore, the psychiatrist inadequately addresses the childhood trauma that serves as the root cause of Kevin’s DID, where the fragmentation of his personality occurred. There is also a notable absence of any discussion regarding medication or efforts toward integration, even when the psychiatrist becomes aware that one of the alters is impersonating another and suspects potential harm via the emerging ‘beast’ alter.
Etiology and Conclusion
Kevin’s Dissociative Identity Disorder (DID) is likely influenced by both environmental and biological factors, as depicted in the movie. According to the Medical Model, particularly the diathesis/stress model, DID can be understood in terms of predisposition (diathesis) and environmental pressures (stress) (Carson, 2025). In Kevin’s case, his predisposition includes high hypnotizability, while the stressors are the repetitive, inescapable trauma he endured.
Kevin’s DID originated at the age of three, primarily as a response to the severe emotional and physical abuse inflicted by his mother. Research indicates that DID is strongly associated with chronic childhood trauma, especially trauma experienced before the age of nine (Dorahy et al., 2014). The film illustrates dissociation as a means for Kevin to escape unbearable trauma, with each alter emerging in response to distinct traumatic events. The alters in DID serve various protective roles, while remaining within the realm of normal human experience (Dalenberg et al., 2012). Kevin conveys that different alters manifested to absorb the psychological and physical pain he was unable to withstand; notably, Hedwig, a child alter, took on abuse when he was just three years old. Kevin’s DID is depicted as a coping mechanism in response to severe childhood trauma.
From a biological perspective, the film features the psychiatrist Dr. Fletcher, who explains how alterations in the human brain can lead to the formation of different alters. While the film presents some scientific truths, it also exaggerates the notion that DID can rewire the brain to unlock “unused potential.” Research by Reinders et al. in 2018 indicates that DID is associated with altered brain function in trauma-related regions, including the hippocampus and amygdala; A reduced hippocampal volume is linked to memory disruption, while a hyperactive amygdala contributes to heightened fear responses and thinning of the Corpus Callosum may facilitate dissociative boundaries between identities (Reinders et al., 2018).
Altered hormonal changes are portrayed in Kevin’s alternate personalities. “The Beast” exhibits a high pain tolerance and superhuman strength, which suggests the presence of an adrenaline or dopamine surge. Another alter, “Dennis,” displays traits similar to obsessive-compulsive disorder (OCD), indicating possible alterations in serotonin levels. Research by Sierra, M., & Berrios, G. E. in 1998, indicates that trauma survivors, including those with Dissociative Identity Disorder (DID), often experience dysregulated stress systems and an overactive HPA axis, resulting in elevated cortisol levels associated with chronic stress. Furthermore, heightened cortisol during traumatic events may hinder memory integration, while dissociation might involve natural pain-relief mechanisms (Sierra, M., & Berrios, G. E., 1998).
In terms of genetic factors, Dr. Fletcher, Kevin’s psychiatrist, speculates that DID could arise from a rare brain adaptation to trauma, which is a fictional exaggeration in the film. However, real-world twin studies suggest heritable tendencies toward dissociation, with trauma being a primary catalyst (Jang et al., 1998).
The film “Split” illustrates the profound childhood trauma experienced by both Kevin and Casey, rooted in an abusive home environment and a lack of care during their formative years. While Kevin succumbs to Dissociative Identity Disorder as a means of escaping his trauma, Casey emerges from her struggles as a survivor. I appreciate how this film serves as a reality check, shedding light on the crimes committed against children and fostering an understanding of their emotions and the potential consequences of harm.
Analysis of ‘CopyCat’ Movie
“Copycat” is a psychological thriller film released in 1995, directed by Jon Amiel and starring Sigourney Weaver. While I’m generally not a fan of films featuring psychokillers, “CopyCat” resonated with me on a different level. Beyond its intriguing plot and compelling screenplay, the movie tells a powerful story about confronting fear and emerging victorious.
At my young age, watching a psychologist, Dr. Helen Hudson, assist the police with her insights into psychopathological behavior inspired me to delve into the field of psychology. This film opened my eyes to the world of psychology and psychopathology. Adding an extra layer of complexity to the storyline is the fact that the antagonist is a psychopath, while the protagonist, the psychologist, grapples with agoraphobia, a type of anxiety disorder that involves the fear of and avoidance of places or situations that may trigger panic, feelings of being trapped, or embarrassment.
Agoraphobia may seem like a benign disorder, but in severe cases, individuals may become homebound and struggle to muster the courage to face the outside world. During the COVID-19 pandemic, I often reflected on the challenges we faced during lockdowns. For those with agoraphobia, however, lockdown is their everyday reality; it’s as if they are under constant home arrest.
In this paper, we will explore Helen’s character, discuss the portrayal of mental disorder in the film, evaluate its alignment with psychological concepts we have studied in class, and analyze potential environmental and biological factors contributing to the disorder.
Plot Synopsis
Dr. Helen Hudson (Weaver), a renowned criminal psychologist and expert on serial killers, was attacked by a psycho killer, Daryll Lee Cullum, at a lecture ceremony. He is a vengeful killer whom Helen once helped convict. The strangling incident traumatized Helen, leading to traumatization and Agoraphobia. One year later, a new killer emerges in San Francisco. This murderer’s killings mimic those of famous serial killers (Jeffrey Dahmer, Ted Bundy, etc).
Inspector M.J. and her partner consult with Helen, and Helen deduces that the murderer is a “Copycat,” someone meticulously recreating past murders with unsettling precision. They join forces to investigate these copycat crimes. The perpetrator leaves clues tied to Helen’s past cases, systematically taunting her. As they analyze the crime patterns, suspicion falls on Peter, a young criminology student who is obsessed with both Helen and Cullum. It is ultimately revealed that Peter is the killer, having disguised himself as an ally to both Helen and M.J. He skillfully manipulates them, exploiting Helen’s phobia to steer the investigation. His motive is to surpass the killers he idolizes and make Helen his final victim.
In a climactic moment, Peter invades Helen’s home, forcing her to confront her agoraphobia. In a desperate attempt to escape, she rushes to the top floor and finds herself cornered. Accepting her grim fate, she succumbs to the situation. Just as he is about to take her life, M.J. appears and shoots him.
In the final scene, Cullum reveals that he orchestrated the attack on Helen, making it appear as though Peter acted independently. He instructs the next ‘disciple’ to follow the plan, emphasizing the importance of simplicity, just kill Helen, rather than striving for the fame of a serial killer. This film portrays its antagonists as idolizers of serial killers, each seeking a similar kind of fame for themselves.
Helen’s Agoraphobia and panic attacks are depicted with great realism, particularly during a scene where she is overwhelmed at the moment of meeting the police officers, leading to a sudden panic attack that causes her to collapse. Her assistant assists her with a breathing bag as a relaxation technique for managing her panic attacks. Though this movie showcases multiple people with mental disorders, this review is centered on Helen’s disorder analysis.
Character Description / Disorder Criteria
Helen’s character exhibits several symptoms consistent with Agoraphobia and Post Traumatic Stress Disorder (PTSD) as defined by Dr. Carson and the DSM-5.
Diagnosis of Agoraphobia
Agoraphobia, as defined by the DSM-5, is an anxiety disorder characterized by significant fear or anxiety related to at least two of the following five situations: using public transportation, being in open spaces, being in enclosed spaces, standing in line or being in a crowd, or being outside the home alone. It is characterized by a marked fear or anxiety, trying to seek an escape from a situation or needing a companion, causing significant distress or impairment that may last for more than 6 months (APA, 2022).
For example, Helen avoids leaving her heavily secured apartment and feels uncomfortable being outside in open spaces, as depicted in the climax of the film. She avoids situations where escape might be difficult and where help might not be available in case of panic symptoms. Helen struggles with meeting new people; during her first encounter with the inspector, she experienced a panic attack. Her anxiety is evident throughout the movie, particularly when confronted with unexpected situations. Additionally, she actively avoids situations or requires the presence of a companion. For instance, she has an in-house assistant whom she depends on, especially when meeting people. Her fear and anxiety are often out of proportion to the actual danger; even stepping out of her door to retrieve a newspaper causes her significant distress. These symptoms have been present for more than six months, as shown in the film. Helen’s anxiety impairs her social life, as she only interacts with people online and avoids in-person meetings. All these points contribute to the diagnosis of Agoraphobia.
Diagnosis of PTSD
According to the DSM-5, PTSD is characterized by the exposure to the traumatic event followed by the presence of intrusive memories, avoidance behaviors, negative changes in thinking and mood, and hyperarousal following exposure to traumatic events that persist for at least one month and cause significant distress or impairment (APA, 2022). Throughout the movie “CopyCat,” Helen demonstrates many of these PTSD symptoms, Traumatic event (The killer strangled her); Intrusion symptoms (She experiences intrusive memories and flashbacks of the trauma); Avoidance symptoms (She avoids reminders of the event, such as refusing to leave her apartment); Negative alterations in cognition and mood (She exhibits a persistent negative emotional state and diminished interest in activities); Alterations in reactivity (She shows hypervigilance and an exaggerated startle response) (APA, 2022). These symptoms persist even a year after her attempted murder.
While the movie portrays agoraphobia, it does not explicitly diagnose Helen with PTSD. However, her symptoms align with both PTSD and agoraphobia, as outlined in the DSM-5. Helen experiences panic attacks, but there are insufficient details in the film to classify her condition as a panic disorder. For instance, there are no recurrent, unexpected panic attacks; her intense anxiety arises when she is forced to leave her apartment and is triggered by reminders of her trauma, rather than occurring unexpectedly (APA, 2022). Additionally, she does not exhibit persistent worry about future panic attacks, as her fear is linked to her agoraphobia and PTSD rather than a generalized fear of panic attacks; her isolation results from avoidance behaviors related to PTSD, not changes in behavior driven by panic (APA, 2022).
Treatment & Research Concepts
The portrayal of PTSD and agoraphobia treatment in the film is notably limited. It fails to reference established therapeutic techniques such as Cognitive Behavioral Therapy (CBT), Dialectical Behavior Therapy (DBT), or Eye Movement Desensitization and Reprocessing (EMDR), which we studied in class (Carson, 2025b). Helen is shown taking medication during a panic episode, likely consisting of benzodiazepines (only during severe symptoms) for acute anxiety and SSRIs or SNRIs (e.g., Prozac, Zoloft) for PTSD and depression, both of which are often associated with Agoraphobia. Though the film does not specify the medication, her reliance on pills suggests a focus on symptomatic management rather than a path to recovery.
In an ideal scenario, the recommended treatment modalities for Agoraphobia and PTSD, according to Dr. Carson’s lecture, would include Cognitive Behavioral Therapy with Prolonged Exposure and Cognitive Restructuring, Skills Training and Stress Management, Mindfulness-based CBT, and Acceptance and Commitment Therapy (ACT); and interventions like Equine-Assisted Therapy for PTSD can be quite beneficial (Carson, 2025a; Carson, 2025b).
Among the various therapeutic approaches, exposure therapy combined with Cognitive Behavioral Therapy (CBT) appears particularly promising for addressing Helen’s Agoraphobia (Hofmann et al., 2012). This exposure therapy process can gradually acclimate her to her fears by taking incremental steps, such as first opening her front door and standing there for a short period. The subsequent steps could involve taking a few steps outside the door or walking down the hallway. Eventually, she could work towards being in crowded settings with strangers and initiating casual conversations (Craske et al., 2014). Similarly, Prolonged Exposure (PE) Therapy can be employed for her PTSD by systematically confronting trauma memories (Powers et al., 2010). In Helen’s case, combining her medication with these therapies would provide a more comprehensive treatment approach. Practicing diaphragmatic breathing when panic symptoms arise would serve as an effective coping skill for her, and maintaining a thought record to identify the specific situations or thought patterns that trigger her panic attacks would be advantageous (Zaccaro et al., 2018).
The film accurately depicts how PTSD and agoraphobia can lead to self-medication and reluctance to engage in therapy. However, it inaccurately represents real-world treatment, as effective recovery would incorporate the aforementioned therapies. Instead, the film illustrates improvised coping mechanisms rather than clinical treatment. Helen’s progress, such as confronting her assailant, is driven by external circumstances rather than psychological healing, presenting a dark yet realistic perspective on untreated trauma.
Etiology and Conclusion
While biological factors like neuroticism, pre-existing mental disorders, and low IQ can contribute to PTSD (Carson, 2025b), in the movie, Helen appears to be suffering from PTSD primarily due to environmental factors. Helen was brutally assaulted and strangled by a serial killer, which meets the DSM-5’s criterion of “exposure to actual or threatened death” (APA, 2022). A study by Breslau et al. (1999) showed that survivors of violent assaults have a 30% lifetime risk of developing PTSD, which is higher than that associated with non-violent trauma. Physical assault victims are more likely to develop PTSD than those involved in accidents (Breslau et al., 1999).
Her Agoraphobia may have originated from trauma-induced avoidance following the traumatic strangulation incident. Due to a fear generalization mechanism, Helen’s PTSD has led her to fear all public spaces, which is a hallmark of agoraphobia, and Trauma can condition fear responses to neutral stimuli, such as open spaces or unfamiliar people (Mineka & Zinbarg, 2006). Helen experiences panic attacks when outside or encountering strangers; however, her Agoraphobia is trauma-driven rather than purely panic-based. According to a study by Wittchen et al. (2010), it is common for PTSD and agoraphobia to coexist, especially in cases involving feelings of entrapment, as experienced by Helen during her assault. Additionally, there may be genetic influences and cognitive factors, such as catastrophic misinterpretation theory, which could lead her to think, “I’ll die if I go out” (Carson, 2025a).
Overall, this movie demonstrates how the impact of near-death trauma can drastically alter a person’s life, from being someone who confidently delivers a speech on stage to becoming homebound and afraid to step outside. It highlights that even a clinical psychologist is not immune to facing a disorder, reminding us that at the end of the day, everyone is human. The suffering depicted in the film emphasizes the need to understand and provide community support to assist patients grappling with Trauma and Agoraphobia.
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