Like many authors, Hawkins takes bits of people’s personalities and infuses them into characters. The major and minor characters interact with each other in various ways throughout the novel. Their connections and motivations are explored in depth as the plot unfolds.
Rachel Watson
Role: Protagonist, Tom Watson’s ex-wife.
Key Info: She is an obsessive alcoholic who solves the mystery of Megan’s disappearance.

In the beginning, Rachel is a divorced, alcoholic woman who recently lost her job. Still, she rides to and from London to distract herself from her loneliness and grief.
In this novel, Rachel is an unreliable narrator. Her sessions of alcoholism usually lead to confusion and blackouts. When she regains consciousness, she fights to differentiate reality from her perceptions.
Rachel also struggles with guilt and embarrassment. Haunted by shame over infertility and her struggles with alcoholism, she feels responsible for the end of her marriage to Tom Watson. Her guilt and shame contribute to her low self-esteem and self-sabotaging behavior.
Her loneliness leads to an obsession with the lives of the people she sees on the train, particularly a couple she nicknames “Jess and Jason.” They live at 23 Blenheim Road, down the street she used to live with her ex-husband, Tom Watson.
One day, she sees the woman in the couple kissing someone else. She is triggered because her ex cheated and eventually married his mistress, leaving her heartbroken. Later, she wakes up to bumps and injuries but cannot remember what transpired to cause the bruises. She finally recollects that the young woman she saw cheating, Megan Hipwell, is missing. Rachel’s inability to recall what happened when Megan disappeared leads her to believe she was involved in a crime.
Her obsession with people, including her ex-husband and his wife, propels her to make impulsive and reckless decisions that have consequences for herself and others. As she strives to put the truth together, she discovers she has sunk into depths of hopelessness and misery. She also realizes her seemingly perfect ex manipulated and lied to her during and after their marriage.
Despite her flaws, Rachel is determined to solve the mystery of what happened to Megan. Her desire for redemption fuels her determination. She also wants to prove she can overcome addiction and be a better person.
Eventually solving the case, she tries to rescue another victim-to-be but kills the murderer in self-defense.
Megan Hipwell (Jess)
Protagonist, Scott Hipwell’s wife. Her death is the primary mystery of the story.
Key Info: Traumatic history, multiple affairs.

Like Rachel, Megan is also a complex character. Trauma from her past life haunts her and makes her impulsive. She is a young and sensitive woman who is unpredictable and lies frequently. She often keeps secrets from those around her, making it difficult to gain trust.
At the beginning of the novel, she goes missing. The plot follows the investigation of her disappearance. With flashbacks, the reader gets information about Megan’s life before and after she goes missing.
She is married to the affectionate but domineering Scott Hipwell. Soon, she becomes frustrated with the requirements of family life. She does not consider motherhood, much to the disappointment of her husband.
When Scott suggests therapy to help improve her sleeping habits, she begins sessions with Dr. Kamal Abdic. She becomes attracted to him and eventually confesses her traumatic past.
In her confession, she has a daughter from a teenage relationship. Accidentally, she drowns the child. Unable to find closure, she chases sexual excitement to escape her emotions. Her search for thrill prevents her from settling into a stable lifestyle or relationship. She changes jobs frequently and has a history of infidelity.
While making countless sexual advances at Kamal Abdic, she begins an affair with Tom Watson. Tom is the father of Evie, a child she used to babysit. Megan’s devastating experiences leave her anxious, desperate, and depressed.
When she turns out pregnant, she informs Tom, but he refuses to take responsibility. Her disappearance at the beginning eventually leads to the revelation of her death.
As the tragic figure in the novel, she is a deeply damaged woman who cannot find a way to heal. Her story is a cautionary tale about the dangers of ignoring emotional needs and the importance of seeking help when struggling with mental health issues.
Anna Watson
Role: Protagonist, Tom Watson’s wife and former mistress.
Key Info: She resents Rachel and eventually faces betrayal.

She is the third narrator that Hawkins uses to push the plot of the novel. She is a minor character with a significant role.
She is married to Tom Watson and is deeply protective of her husband and child. A mistress turned wife, Anna feels insecure about Rachel’s constant interference in their family life. She feels uncomfortable with Rachel roaming around the house and calling Tom at odd hours.
Anna devotes time to domesticity to divert her attention from her actual desires and fears. She misses her work as a real estate agent and does not fully trust Tom. She lies to herself constantly and tries to convince herself her only problem is Rachel Watson.
When her former nanny, Megan, disappears, she is concerned about the inability of the police to expose the culprit. Self-absorbed and concerned with public validation, she struggles to be happy. She also hates the location of her house but chooses to stay because her husband insists.
Anna’s character serves as a foil to Rachel, who is unstable and unreliable due to her struggles with alcoholism and her obsession with Tom. Anne’s faux confidence and put-together demeanor highlight Rachel’s flaws and make her seem even more vulnerable in comparison.
When she stumbles on Tom’s gym bag containing Megan’s phone, she is devastated but does not confront Tom. When Rachel visits to expose the truth about Megan’s death, although she knows it is true, she refuses to believe it to protect her family’s “perfect” status. When Tom confesses to the murder of Megan, she chooses to support his side of the story.
Eventually, however, she joins Rachel in killing Tom.
Tom Watson
Role: Antagonist, husband of Anna Watson, ex-husband of Rachel Watson.
Key Info: He is manipulative and unfaithful.

He is the ex-husband of Rachel Watson, and the current husband of Anna Watson. Initially, he is a handsome, charming man into real estate and serious about his family. As the story progresses, however, Tom is exposed to be a manipulative, dishonest, and dangerous antagonist.
While married to Rachel, he gaslights her into believing he is a victim whenever she gets intoxicated. Tom accuses her of physical and verbal abuse. However, he gets exposed as a liar and manipulator.
All that time, he was the one who brutally abused her when she was drunk, confident she would not remember. His infidelity and abuse of women eventually lead to the breakdown of his marriage to Anna.
Tom is heavily involved in the novel’s mystery, which revolves around the disappearance of Megan Hipwell. While married to Anna, Tom begins an affair with Megan and is the last person to see her alive. As the story progresses, it becomes clear that Tom’s involvement in the case is more complex than it initially appears.
When Rachel remembers all the details of the night Megan was killed and confronts Tom, he confesses to killing Megan, then attacks her. He gets killed by Rachel in self-defense.
Scott Hipwell (Jason)
Role: Husband of Megan Hipwell, a suspect in Megan’s murder.
Key Info: He is controlling and protective. He is distraught when Megan goes missing.

Scott is the husband of Megan Hipwell. He becomes emotionally downcast when Megan disappears.
When the novel begins, he is an IT professional devoted and caring, yet controlling of Megan. He monitors her whereabouts and communication. Scott’s domineering nature fuels her yearning to flee her marriage and London. Scott’s love and dedication to Megan and her flippancy and fear of motherhood spurn the need to be overprotective within him.
When Megan dies, he is a primary suspect. As he tries to uncover the truth about his wife’s death, he has to confront his shortcomings as a husband. While working with the police to unravel the mystery surrounding Megan’s disappearance, he begins to piece together the events leading up to her death. He comes to a greater understanding of his role in their relationship.
He accepts support from Rachel when she reaches out to him as an acquaintance of Megan. One day, they drink too much and have sex. The comfort Scott feels in Rachel’s presence dies when he realizes she lied about knowing Megan. He harasses her and holds her hostage for a while before letting her leave.
Kamal Abdic
Role: Supporting character, Megan’s therapist.
Key Info: He faces ethical challenges when Megan makes sexual advances at him. He becomes a suspect when Megan disappears.

He is a Muslim migrant from Bosnia. He works as a therapist in Witney. When he meets Megan Hipwell, she is distressed and fidgety. He tries to help untangle the trauma of her past life and the effects on her current life.
Kamal is a quiet man who is easy to confide in. Soon, Megan becomes romantically attracted to him. He resists her advances, stating it was natural because he was helping her work through her struggles.
Kamal gets arrested briefly as a suspect when Rachel identifies him as Megan’s lover. When the police cannot provide enough evidence against him, however, they set him free.
Rachel begins therapy with him to restore her memory and confirm his innocence. During her sessions, she confides in him about her struggle with infidelity, her attachments to alcohol, and her failed marriage with Tom.
An empathetic and meditative man, Kamal Abdic is a victim of wrong perception in “The Girl on the Train.”
Cathy
Role: Secondary character, Rachel’s flatmate, Damien’s girlfriend.
Key Info: She is supportive of Rachel. She is loyal and patient.

By giving Rachel a place to live after her divorce, Cathy provides some balance in her life while depression and alcoholism get the best of her. Rachel is confident in her support and loyalty as they have been friends since university.
As Rachel’s mental disorder continues to deteriorate, Cathy loses her patience and asks her to leave. However, she changes her mind and remains empathetic. Although her boyfriend asks that she stop being supportive, she is determined to save Rachel from her addiction. Through Cathy ”The Girl on the Train” explores themes of friendship and loyalty.
Detective Inspector Gaskill
Role: Secondary character, Inspector in charge of Megan’s case.
Key Info: Persistent, skeptical, and rational.

When Rachel meets him at the early stage of Megan’s disappearance, Gaskill distrusts her movements and mental state. His skepticism adds to the suspense, forcing Rachel to confront her addiction and memories. After a while, his suspicion shifts to Scott as new information about his abusive tendencies is released. Gaskill’s neutral yet firm approach highlights the difficulty of discerning the truth when lies, emotions, and deception distort the facts. When Rachel kills Tom in self-defense, he arrives with Detective Riley to investigate. When he is satisfied with her narration, he lets her go.
Detective Sergeant Riley
Role: Supporting character, Police Officer investigating Megan Hipwell’s homicide.
Key Info: Works with Detective Gaskill, skeptical of Rachel Watson’s credibility due to her unpredictability.

Like Gaskill, she is suspicious of Rachel. However, she is less empathetic and decides Rachel keeps interfering in the case because she is depressed and desperately wants to be a part of something. Her dismissive attitude is because of Rachel’s agitation and erratic behavior. Not only does Rachel struggle to recall events, she also has to deal with disbelief.
Tara Epstein
Role: Secondary character, Megan’s friend.
Key Info: Supportive, secretive, assists Megan.

She is single and around forty years of age. Tara’s actions represent the complexity of loyalty, especially when it involves dishonesty. Megan uses the excuse of meeting with Tara to get out of the house and meet her lover. Tara does not mind lying and tells her about Scott’s suspicions. When Megan goes missing, she says Scott is innocent.
Damien
Role: Secondary character, Cathy’s boyfriend.
Key Info: Critical of Rachel.

Although a secondary character, Damien represents society and the external judgment Rachel faces, presenting a sharp contrast to Cathy’s supportive nature. He constantly complains about Rachel to Cathy. When Cathy asks about hooking Rachel up with a guy from work or his rugby team, Damien says nobody is that desperate. His relationship with Cathy does not seem to progress as they have been dating for almost two years, yet he has never introduced her to his mom.
Andy
Role: Secondary character, Redheaded man who unsettles Rachel.
Key Info: Minor yet memorable presence. He provides details to help Rachel remember her actions the night Megan disappeared.

Andy is the redheaded man who lives in the London suburb of Witney. He rides the train like Rachel, and she is frightened of him. When he tries to be friendly, she is wary. After her blackout close to the train station, she remembers Andy helping her to her feet and fears he attacked Megan. Andy eventually proves to be simply free-spirited and innocent. Seeing Andy from only Rachel’s point of view enhances the tension, showing the fragility of perception.
Evie Watson
Role: Minor character, Tom and Anna’s infant daughter.
Key Info: She depicts familial stability.

Evie’s role is more symbolic than active. Her presence in her buggy when outdoors demonstrates domestic control, unity, and perfection. In the latter part of the book, Evie contributes to the strain in Anna and Tom’s relationship. Evie represents motherhood, contrasting Megan’s child loss and Rachel’s inability to conceive.
Elizabeth (Libby)
Role: Minor character, Megan and Mac’s daughter.
Key Info: She is involved in a tragic accident that haunts Megan.

When Elizabeth is only a few months old, Megan takes her for a bath. Unfortunately, she falls asleep, and Libby drowns. Elizabeth’s death adds depth to Megan’s character. Megan’s unresolved guilt over the death causes her aversion to children and childcare. Her character explores how grief can lead to damaging coping mechanisms. Elizabeth, though only mentioned in flashbacks, becomes a symbol of everything Megan lost.
Craig McKenzie (Mac)
Role: Minor character, Megan’s ex-boyfriend, Libby’s father.
Key Info: He is Megan’s former lover.

Mac was Megan’s lover when she was a teenager. They had a child together, but she died. After helping Megan bury her body, he abruptly leaves and is not heard or seen again. When Megan dies, the police investigate him but realize he is dead. Megan’s relationship with Mac symbolizes the attractiveness of freedom and the realities that accompany poor choices.