Married British naval captain Nelson falls in love with the wife of the English ambassador to Naples after she helps him in his war duties.
At Calais Emma (Vivien Leigh) is caught stealing a bottle and in jail tells her story. At age 18 Emma in Naples visits British ambassador William Hamilton (Alan Mowbray), who dines alone with her. William tells Emma that his nephew will not marry her. She cries, but William offers her a home and education. Emma marries William and tells her mother she is happy. Emma meets Captain Horatio Nelson (Laurence Olivier), who says they are at war with France. Emma helps him see the Queen of Naples to get 10,000 troops.
Five years later Emma comes aboard Nelson's ship, sees his blind eye, and helps him get supplies. Nelson comes to the Naples king to warn them and then collapses ill before Emma. She cares for him in her bed. Nelson asks her to write his letter to his wife praising Emma. In a tavern Nelson tells her he is in love and sees his step-son Josiah (Ronald Sinclair) mocking William. Josiah writes to his mother about "that Hamilton woman." William tells Emma that Nelson is leaving, and Emma quarrels with William. Emma finds Nelson and kisses him goodbye. Nelson orders a blockade of Malta and goes back to rescue Naples. The British admiralty recalls Nelson to London. Emma gambles with Nelson. William warns Emma that Nelson must not disobey and says she must go to Cairo. Nelson tells Emma that he must go alone. On the last day of 1799 they kiss.
Lady Nelson (Gladys Cooper) arrives in London with Nelson's father (Halliwell Hobbes). Lord Spencer (Gilbert Emery) of the admiralty tells Lady Nelson that Nelson arrived with a woman and is on leave. People celebrate Nelson, and William comes in. Nelson kisses his wife on the cheek, and Emma comes in. Lady Nelson tells Emma that Nelson will be better in Norfolk. Nelson tells Emma that they can get divorces, but she says it is wrong. Nelson speaks in the House of Lords. Nelson goes to his wife; but Emma collapses, and Lady Nelson leaves without her husband. Nelson complains and quarrels with his wife, who says she will leave and never divorce. Nelson's father cannot get him to go to her and stays with Lady Nelson.
In 1801 Emma registers her child with Horatio as father. Emma's mother tells her that William lost his goods on a ship, and demented William dies. Nelson defeated the Danes and warns against peace with Napoleon. Nelson calls on Emma and wants to see her child, but she says no. He asks to see her letters, and she says they are bills. Nelson gives her a home. Hardy (Henry Wilcoxon) tells Emma they need Nelson against Napoleon. She sees his plan of defense and tells Nelson to go to the admiralty. In 1805 at Trafalgar Nelson commands the fleet but is shot as they defeat the French and Spanish. Nelson is paralyzed and dies. Hardy tells Emma of the victory and says that Nelson's last thought was for her. Emma collapses. In the jail old Emma says there is nothing after that.
Winston Churchill had his favorite film produced as
a morale booster for the British in the war against Hitler's tyranny,
although in addition to its propaganda, Admiral Nelson's roving
symbolizes the militaristic imperialism that clashed with France's.