Ever since her husband Tom left her for another woman, Rachel’s life had been a sad, drunken mess. She’d lost her job at the PR firm. She could not survive a day without downing alcohol, or leaving hysterical messages on Tom’s voice mail, or standing outside their old house just to get a glimpse of him. She’d been renting a small room at her friend Cathy’s apartment after she was forced to leave their marital home. Tom’s new wife, Anna, and their baby girl Evie, lived there now. The past few months had been the saddest and the most difficult, and Rachel simply just could not deal.
To establish a routine of sorts, every day she takes the 0804 train from Ashbury to Euston, and the 1756 going back. Cathy has no idea she’d been jobless for weeks. She’ll just deal with that when she’s ready, or sober. In the meantime, Rachel kills time inside pubs, getting drunk as a skunk. She knows things have gotten out of control, but she does not know how to stop. She does not know if she even wants to.
All those times she took the train to the city and back, Rachel has grown a fascination with the couple who lived beside the train tracks, just a few doors down from their old house on Blenheim Road. She calls them “Jess and Jason”; they look like a Jess and a Jason. She is beautiful and elegant, and he is tall and handsome. They are young, successful, happy, and totally in love. Rachel rooted for them, hoped that they won’t end up like her and Tom. She always looked forward to seeing them on their balcony while they shared a glass of wine or read the morning paper together.
One day, while sitting on her usual window seat on the train, Rachel sees Jess kissing another man. It is a hot and passionate kiss, not like the ones she shared with Jason. A few days later, Jess is reported missing. Shortly after that, her body is discovered in a shallow grave not far from her house.
Rachel is devastated by her death and is convinced that she was killed by someone who knew her. She also knows that Jess was having an affair before she died and that the police were questioning the wrong man. Driven by her desire to help with the investigations, Rachel decides to come forward with this information, but ends up being more entangled in this deadly mystery than she ever realized.