Richard Machen, a naval officer of American descent serving under Lord Nelson, and heiress Jane Ashford, duel alone in Napoleonic Europe to foil the Illuminati's subversive plot for world power. Passing through London to visit his old home before sailing to Boston, Massachusetts after the defeat of the French at the "Battle of the Nile," Richard is drawn into a fateful chain of events that will affect history, involving Colonel Despard, an Irishman who is masterminding a radical plot to assassinate the King of England and overthrow the government, turning Britain into a republic. But Despard's plot is being manipulated by the Illuminati, a secret society who orchestrated the French Revolution, and are conspiring to regain control of France from the rule of its First Consul, a despotic young General called Napoleon Bonaparte, who is himself planning to invade England in his own desire to conquer all of Europe and then the world. Machen, together with Jane, foil Despard's plan, and he and his secret committee are brought to trial for treason. They are found guilty and due to the non-intervention of Lord Nelson, once a combatant friend of Despard's, are executed and beheaded. But this is not the end of the Illuminati's or Napoleon's greater ambition. It continues, driven on by Conor Macnamara, an Irish revolutionist and a member of the Illuminati, who has sworn to kill Nelson in revenge for the death of his brother, a member of Despard's committee. And Admiral Nelson is the only one standing in the way of France's invasion of England, with a sea battle to be decided between the English and French Fleets in the Bay of Trafalgar off the west coast of Spain. Will Machen and Jane save the day - and also help shape history by discovering the Illuminati's secret code and bringing about their downfall?