Fact1: Rachel During became depressed about infertility marriage, Fact2: Rachel Scott pretending to be friend to tell him about affair, Fact3: Tom had been fired for having sex with coworkers, Fact4: Anna finds secret phone with text messages on it to woman, Fact5: women confront him with details of affair with Megan
Output: Rachel Watson is an alcoholic who rides a train aimlessly since losing her job. From the train, she fixates on the lives of her former husband, Tom Watson, and his current wife, Anna, and their neighbors, Scott and Megan Hipwell, whom she idealizes. Megan worked for the Watsons as a nanny, but recently quit. During her marriage, Rachel became depressed about her infertility and developed a drinking problem that has resulted in continual blackouts and destructive behavior. At a BBQ held by Toms boss, she drunkenly made a scene and is blamed when Tom is fired. From the train, Rachel spots Megan kissing a stranger and becomes infuriated at her ruining her marriage. She leaves to confront Megan, but hours later she wakes up in her bed, covered in blood. Megan disappears and Rachel is questioned by Detective Riley because she was seen in the vicinity that day. Rachel contacts Scott, pretending to be a friend, to tell him about the affair. Scott pulls up a picture of Megans psychiatrist Dr. Kamal Abdic, and Rachel identifies him as the man she saw. It is alluded to that Megan and Dr. Abdic were involved sexually. Dr. Abdic told the police Scott was abusive and suspicion shifts to him. Believing Dr. Abdic is involved in Megans disappearance, Rachel schedules an appointment with him, but discusses her own issues. Megan is found dead and tests show she was pregnant, but that neither Scott nor Dr. Abdic were the father. Scott confronts Rachel for lying to him about knowing Megan and angrily grabs her. Rachel goes to report the assault, believing Scott murdered Megan, but the detective says he has been ruled out as a suspect. On the train, Rachel sees Toms former bosses wife Martha, and apologizes for her behavior, but Martha says she did nothing wrong. Tom had actually been fired for having sex with coworkers. Rachel realizes that Tom planted false memories in her head during her drinking binges. Anna suspects Tom of cheating and finds a secret phone with text messages on it to another woman, who is revealed to be Megan when Anna calls and hears the voicemail. Rachel goes back to the tunnel and in a flash back remembers that she caught Tom meeting Megan that day, and that Tom attacked her, injuring her. Rachel goes to warn Anna, and tells her Tom is dangerous and he killed Megan. Anna knows about the affair and when Tom arrives home, both women confront him with details of the affair with Megan. Tom knocks Rachel unconscious and in a flash back, it is revealed that Tom beat Megan to death when she announced her pregnancy and refused to get an abortion. When Rachel awakens he tries to strangle her, but she gets away. Tom chases her and she stabs him in the neck with a corkscrew, and Anna twists it deeper into Toms neck, killing him. Rachel and Anna are interviewed by Detective Riley, and tell identical stories about killing Tom in selfdefense, after he admitted to being Megans killer. Later, a now sober Rachel sits on the opposite side of the train looking forward to the future.