The widow Dr. Lewis Shaler and his son Max are traveling late night by train to London. Lewis will leave Max with his grandparents to attend victims of a great accident at the hospital where he works. When Max accidentally spills coffee on the coat of the promoter Sarah Barwell, Lewis is embarrassed and offers to pay for the cleaning of her coat. Soon they start a conversation and feel attracted for each other. When the train stops, Lewis sees a man on the track apparently fixing the brakes. When the trains moves, he sees another man crawling on the tracks. Lewis seeks out the train guard and finds that he is missing. Further, the train does not stop at the stations. He tries to contact the driver that asks how many passengers are still on board and nothing else. Lewis contacts the passengers Jan Klimowski, Peter Carmichael and Elaine Middleton and they team-up expecting to stop the train. Soon they conclude that the train has no brake and the driver is a suicidal. What will happen to them?