The story is set in winter in 1906. After his adventures as an amateur sleuth, Jim Stringer is now an official railway detective, working from York Station for the mighty North Eastern Railway Company. But he's not a happy man. As the rain falls incessantly on the city's ancient, neglected streets, the local paper carries a story highly unusual by York standards: two brothers have been shot to death. Meanwhile, on the station platforms, Jim Stringer meets the Lost Luggage Porter, humblest among the employees of the North Eastern Railway company. He tells Jim a tale which leads him to the roughest part of town, a place where the police constables always walk in twos. Jim is off on the trail of pickpockets, 'station loungers' and other small fry of the York underworld. But then in a tiny, one-room pub with a badly smoking fire he enters the orbit of a dangerous, disturbed villain who is playing for much higher stakes.