Harold Christie - wealthy estate broker and close friend of Sir Harry Oakes Freddie de Marigny - son-in-law of the victim who became the prime suspect Nancy de Marigny - Freddie’s wife who hired private detectives Miami detectives Captain James Barker and Captain Edward Melchen - responsible for serious flaws during investigation The Duke of Windsor - formerly King Edward VIII and resident on Nassau Island Axel Wenner-Gren - rich businessman associated with the Nazi party Frank Marshall - mobster and criminal linked to the Mafia