Having done her Christmas shopping and on her way to visit her friend Miss Marple, Mrs. McGillicuddy relaxes on the train. Then another train, travelling in the same direction on another line draws abreast and for a few minutes the two trains proceed side by side. But in a first class carriage of the second train, Mrs. McGillicuddy┬á sees, to her horror, a man strangling a woman…then the second train gathers speed and vanishes into the night. Miss Marple will believe her, even if the guard doesn’t!┬á Miss Marple telephones her friend Lucy Eyelesbarrow and asks her to go undercover to investigate and Lucy quickly accepts the challenge. Who is the dead woman? What was the motive for her murder? And why was the body thrown from the train and later hidden at Rutherford Hall? When a second murder takes place, everyone at Rutherford Hall is now in danger…