Colonel Aubrey Tarleton is a man respected by his neighbors in the small Yorkshire village of South Otterington as much for his heroic feats in the army as for his social position. So the community is left stunned when Tarleton, deliberately, walks into the path of a speeding train. He is crushed to death on the track, but it is not his broken limbs that attract the attention of the train driver; rather, it is the note pinned to his chest, fluttering in the breeze: 'Whoever finds me, notify Superintendent Tallis of the Detective Department at Scotland Yard'.The famous Railway Detective, Inspector Robert Colbeck, finds his superior officer in great distress when he arrives at the Yard the following morning. Tallis is clutching a letter from his now deceased friend.