In 1804 was discovered an attempt of coup d'etat against Napoleon, who then held the post of first consul. The responsibility of organizing the plot was attributed to the Duke of Enghien Louis Anthony Henry of Bourbon, the last descendant of the family Cond , who lived in exile in Baden and who was done by the French secret service, to be judged in Paris by a military tribunal, chaired by the General Pierre Augustin Hulin. The duke always declared to be innocent, but he was condemned to the firing squad, while the other 42 plotters, finished on trial and then in prison. "The Port of Calais" is a reconstruction of the episode, made from an unusual point of view, the view of the Count Alain de Savoia-Soissons, colonel of the French Navy and a cousin of the Duke of Enghien. During the organization of the conspiracy Alain meets in an inn of Calais Juliette the last Marquis De Sade's daughter, forced into prostitution after the arrest of her father...