When young Dr. Jardine discovers a dead body he promptly reports it to the police, only to find the body gone when they investigate. Later, three mysterious attempts on his own life are made. Why is someone trying to kill him? Is the reason related to the missing corpse or to some other factor? What is the significance of the reliquary he found at scene of the missing body? These are the questions that Dr. John Thorndyke, noted lecturer in forensic medicine, must unravel in A Silent Witness.