The Hand of Power — Edgar Wallace

Dr Joshua Laffin wants Betty Carew, whose childhood he tortured with fear, to advertise a desk for sale. For four hours each day she is to sit at it pretending to write, in a shop window laid out like a study. While she acts this role she is told to wait for someone to approach her. Pawter of Pawter Intensive Publicity Services wants Bill Holbrook to find out more. Bill suspects trouble. He claims someone told him that the desk was invented by a butler who was hanged for murdering his wife...