Dr. John Paterson, head of the combined geology and geography department at Minstow College, was a most unpopular man. Disliked by his students for his pomposity and loathed by his colleagues for his maliciousness, he had few friends. So when his body was found on a ledge half-way down a cliff, while his van was parked above, few people mourned his death. Nevertheless, the local police suspected foul play for Paterson was not the kind of man to take his own life and he had made several enemies including Ronald Grimshaw, the deputy head of his department and William Appleton, the principal. As events proved conclusively that a murder investigation was necessary, Detective Chief Superintendent Tom Pollard and Detective Inspector Gregory Toye arrived from Scotland Yard and found that John Paterson"s death was to become one of the most interesting cases of their careers.