Yorkshire 1855. Colonel Aubrey Tarleton is well respected by his neighbours in the village of South Otterington, so the community is stunned when he deliberately walks into the path of a speeding train. Pinned to his chest is a note for his friend, Superintendent Tallis of Scotland Yard. Then Tallis receives a letter from Tarleton stating he no longer wishes to live without his beloved wife, who has vanished. Was Tarleton responsible for his wife's disappearance and was his suicide the act of a guilty man? Tallis, accompanied by Inspector Robert Colbeck, the famous Railway Detective, sets out for Yorkshire determined to uncover the truth.