From the master of edge-of-your-seat suspense and bestselling psychological thrillers comes a cinematic, locked-room historical mystery filled with dizzying twists. In 1954, a grief-stricken woman named Anna Matheson boards a privately commissioned, luxury overnight train bound from Philadelphia to Chicago. Trapped on board with her are six carefully selected passengers whom Anna holds responsible for orchestrating a tragic act of sabotage during World War II that shattered her family and destroyed her life. Her cold, calculated plan is straightforward: force a confession from the conspirators and hand them over to law enforcement waiting at the final station. However, her quest for justice takes a terrifying turn when one of her targets is found brutally murdered before dawn. Realizing that a separate, ruthless killer is hidden among them executing an independent plot of retribution, Anna must navigate an intricate web of secrets and lies. In a sharp twist of irony, she is forced to protect the very people she came to destroy to keep them alive long enough to confess before the train reaches its destination.