In 1815, following his final defeat at Waterloo, French emperor Napoleon Bonaparte arrives at St. Helena, the barren, wind-swept South Atlantic island to which the British and their allies have exiled him. Guarding Napoleon are troops led by English general Sir Hudson Lowe, the island's governor. Although Lowe allows Napoleon and his small entourage¿his valet, Haitian bodyguard General Gourgaud, and chief aide Count Bertrand and Bertrand's wife¿to move freely around the island, Napoleon bristles at the idea of being Lowe's prisoner. Also assigned to keep an eye on Napoleon is Barry O'Meara, a young doctor who volunteered to be the emperor's physician at St. Helena. Lowe admonishes O'Meara, a fellow Irishman, not to fall under Napoleon's spell, but the brash, idealistic O'Meara dismisses the governor's concerns. Lowe, who despises Napoleon, instructs O'Meara to drop in on the emperor at least once a day and report any significant bits of conversation he might overhear while in Napoleon's company. Napoleon, meanwhile, wastes no time plotting his escape with Gourgaud, who prior to arriving on the island had arranged for a Dutch ship to pick them up and return them to France. In anticipation of the ship's arrival, Napoleon flirts with Betsy Balcombe, the wild young daughter of a local British merchant, who offers to steal a map of the island for Napoleon. After bathing nude in the ocean with Madame Bertrand, Napoleon then reminisces with his former mistress, whose son was killed while fighting with Napoleon's army. While the embittered Mme. Bertrand dreams of having another child, Napoleon reveals that his wife no longer allows their son to speak of him. Later, Napoleon cajoles Betsy, whose parents abuse her, into taking him to see Longwood, the bleak cliff top mansion that is to be his permanent home. Afterward, Napoleon suffers a dizzy spell in front of O'Meara. Concerned, the doctor asks Lowe to postpone Napoleon's transfer to Longwood, but Lowe refuses to wait. Despite being drawn to Napoleon, O'Meara argues with him about his love of war and lust for power. Unfazed by the Irishman's criticism, Napoleon insists he made France the greatest country in the world and sacrificed his men only when necessary. Soon after, Napoleon tricks O'Meara into believing he is in his cottage writing and, with Gourgaud, begins his escape from St. Helena. Lowe captures Napoleon on the beach and orders Gourgaud executed for killing one of his soldiers. Lowe then sends Napoleon and his remaining entourage to the damp, rat-infested Longwood, where the emperor's health continues to decline. Again, O'Meara complains to Lowe about Napoleon's treatment, and Lowe, who believes that the emperor will soon be sent to England to stand trial for war crimes, agrees to make improvements. Napoleon, meanwhile, resumes his affair with Mme. Bertrand, who takes pleasure in his powerlessness while lamenting her own failed life. Napoleon also seduces the eager Betsy, advising her to use men to her benefit when necessary. Later, a British soldier in Napoleon's employ secretly informs the emperor that the French are rising up in Paris against their occupiers. Soon after, Lord Sissal, an elderly English diplomat, arrives on the island. In private, Sissal offers Napoleon a chance to return to France to quell the uprising, in exchange for declaring war on Prussia. When Napoleon demands the right to invade Austria, too, Sissal balks and threatens to go through with the trial if Napoleon refuses to follow his plan. Desperate for freedom, Napoleon accepts the diplomat's terms, and Mme. Bertrand mocks him for "dancing to Sissal's tune." Although O'Meara tries to convince Sissal that Napoleon, who has stomach cancer, is not well enough to travel, both men are anxious to depart. As Sissal is boarding his shore-bound carriage, Napoleon gives him an ornate Russian clock decorated with an eagle, his favorite symbol of power. Seconds later, Napoleon collapses and falls from his horse in a stupor. Sissal promises Napoleon that his offer "still stands," then allows the ailing emperor to be carried back to Longwood.