Rachel takes the commuter train to work every day, dreaming about the seemingly perfect couple she watches from the window in a house she used to live near. One day, she witnesses something shocking in their yard. When the woman from the house goes missing, Rachel goes to the police with what she saw, only to realize her memory of the night is unreliable due to her struggles with alcohol. As the investigation deepens, Rachel becomes entangled in the mystery, desperately trying to piece together the truth of the disappearance and her own actions that fateful night. The thrilling psychological suspense novel explores themes of voyeurism, memory, and self-deception as Rachel races against time to uncover what really happened.