Four strangers on a train. An unlikely introduction: 'Actually, I'm a murderer.' Set in the north-east of England in the seventies, the lives of four people are thrown into turmoil when sharing a carriage with an unremarkable little man with round glasses, on the night train back to Newcastle. By the end of the following day, one of them will be dead, one will turn blackmailer and another forced to commit a crime. And all of them will be under the astute and watchful observation of Aline, the local police officer with her own agenda to fulfil. And then the body count begins to rise which begs the question - just how many actual murderers are out there - and who will be the next victim?