<P> 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 Tom's neck, killing him . </P> <P> Rachel and Anna are interviewed by Detective Riley, and tell identical stories about killing Tom in self - defense, after he admitted to being Megan's killer . Later, a now sober Rachel sits on the opposite side of the train looking forward to the future . </P> <Ul> <Li> Emily Blunt as Rachel Watson, a lonely alcoholic and Tom's ex-wife </Li> <Li> Rebecca Ferguson as Anna Watson, a real estate agent and Tom's current wife </Li> <Li> Haley Bennett as Megan Hipwell, Scott's wife </Li> <Li> Justin Theroux as Tom Watson, Rachel's ex-husband and Anna's current husband </Li> <Li> Luke Evans as Scott Hipwell, Megan's husband </Li> <Li> Allison Janney as DS . Riley, a detective </Li> <Li> Édgar Ramírez as Dr. Kamal Abdic, Megan's psychiatrist </Li> <Li> Lisa Kudrow as Martha, the wife of Tom's former boss </Li> <Li> Laura Prepon as Cathy, Rachel's college friend, roommate and landlord </Li> <Li> Darren Goldstein as Man in the Suit, a stranger who witnesses Rachel's behavior </Li> </Ul> <Li> Emily Blunt as Rachel Watson, a lonely alcoholic and Tom's ex-wife </Li>

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