After boarding a train at Paddington Station, Elspeth is certain she saw a man strangling a woman in an adjoining train. No one else believes it ever really happened--except her friend Miss Jane Marple. And the indomitable sleuth is returning to the scene of the crime to discover just exactly what Elspeth saw. Elspeth McGillicuddy was not a woman usually given to hallucinations. But when she witnesses what appears to be a woman being strangled on a train and no-one else sees it, no-one reports it and no corpse is found she turns to her old friend Jane Marple to help solve the puzzle. Marple asks her highly efficient and intelligent young acquaintance, Lucy Eyelesbarrow to infiltrate the Crackenthorpe family, who seem to be at the heart of the mystery, and help unmask a murderer.