A Harley Street dentist is discovered dead with a gunshot wound, a pistol at hand, leaving investigators to believe a patient's subsequent death from anaesthetic poisoning closes the case as murder and suicide. Yet Poirot recognizes the inconsistencies in this neat conclusion, questioning why a busy dentist would commit such a crime during office hours. A discarded shoe buckle becomes the crucial clue that unravels a far more sinister plot lurking beneath the surface.
