There was something unique about the Case of the Treble Twist. It isn't often one gets a preview of a case or hovers round its fringes four years before it breaks, but that was just what happened here. The preview began the evening Ludovic Travers had a drink with Chief Inspector Jewle, and first heard the name of Harry Tibball, suspect involved in a series of big-scale robberies, Then a few months later Tibball's body was found in a wrecked car not far from a newly burgled house in Bedfordshire. The surviving accomplice was caught and gaoled, but nothing was recovered and nothing more discovered concerning Tibball's past history. Three years went by, and Travers had virtually forgotten the whole business when a pleasant-voiced woman from America rang the Broad Street Agency and asked him to undertake a highly confidential assignment. It proved to be a voice from the past, for it belonged to the daughter of the last man Tibball had robbed.