Rachel Watson, the protagonist, is an unemployed alcoholic whose life spirals downward after her divorce from Tom. She rides the same train daily, passing by her old neighborhood where Tom lives with his new wife, Anna, and their child. She also becomes fascinated with a seemingly perfect couple, Scott and Megan Hipwell, whom she observes from the train window. However, when Megan suddenly disappears, Rachel’s interest turns into an obsession, drawing her into a dangerous web of lies and betrayal.

Rachel frequently blacks out from drinking, leaving her memories unreliable. One night, after seeing something unusual near the Hipwell residence, she wakes up bruised and with no recollection of what happened. Determined to piece together the truth, she contacts Scott, pretending to be Megan’s friend to gain his trust. Meanwhile, Anna is deeply resentful of Rachel’s lingering presence in their lives, fearing for her family’s safety.

Megan’s narrative unfolds in the past, revealing her troubled past, affairs, and secrets, including an illicit relationship with her therapist, Dr. Kamal Abdic. As Rachel investigates further, she becomes a prime suspect due to her erratic behavior and past harassment of Tom and Anna. However, as she regains fragmented memories from the night of Megan’s disappearance, she realizes she has been manipulated all along.

In a shocking revelation, Rachel remembers witnessing Tom attacking Megan. She confronts him, leading to a dangerous confrontation where he attempts to silence her. In an act of self-defense, Rachel and Anna work together to overpower and ultimately kill Tom, bringing the horrifying truth to light. The novel concludes with Rachel finally breaking free from the toxic hold of her past and seeking a fresh start.

Paula Hawkins masterfully crafts an intricate thriller that explores the fragility of perception and the devastating consequences of lies. The novel’s multiple viewpoints offer a deep dive into the minds of three women entangled in a haunting mystery, making The Girl on the Train a compelling and unforgettable read.