Don Juan gives up romance in order to serve the queen of Spain, but he has to overcome the warmongering Duke de Lorca, who controls the king.
Don Juan (Errol Flynn) climbs into the room of Catherine (Mary Stuart) and kisses her. Her husband comes in, and Juan defeats him with a sword. Juan flees with Leporello (Alan Hale) and pretends to be a duke to gain an escort into London. Lady Diana (Helen Westcott) does not want to marry a duke she has never met. She remembers Juan, though he has forgotten her. The duke arrives, and Juan is arrested. He is paroled to the Spanish ambassador, Count de Polan (Robert Warwick), who gives him a letter to Queen Margaret.
Juan and Leporello go to Madrid. At an inn soldiers try to recruit two men forcibly, and Juan fights them with his sword. The Duke de Lorca (Robert Douglas) tells King Phillip III (Romney Brent) to sign a paper to get money from Count de Polan for the navy. Queen Margaret (Viveca Lindfors) argues with the weak King. Juan presents the letter to the Queen, who says he is notorious. Lorca dislikes Juan and leaves with the King. Queen Margaret appoints Juan fencing instructor. Lorca has Polan arrested and demands his money, threatening torture.
Juan's fencing class demonstrates before the court. Juan gives Margaret a tour, and they become friends. Lorca offers Juan a commission in the navy, but Juan does not like war. Juan tells Margaret that she needs protection. He says he loves a virtuous queen, and she dismisses him. Women watch Juan's fencing class, and Elena (Ann Rutherford) tells Juan where she lives, leaving her fan. Juan lounges with Elena in her garden. She says her wedding is tomorrow, and her fiancé, Count D'Orsini, duels with Juan.
Elena tells the Queen what happened, and the King and Lorca tell Margaret that Juan is banished. Juan goes to the inn. Captain Alvarez (Raymond Burr) tries to sell the ring he took from Polan. Juan identifies it and goes to the Queen; but he is captured by Lorca, who deposes the Queen and says he controls the King. Alvarez shows the tortured Polan to Juan in jail. Leporello, disguised as a friar, helps Juan escape. They rescue Polan, and Juan kills Alvarez in a sword duel. Juan tells his students they must arouse the people. The midget Sebastian (Jerry Austin) begs Juan to rescue the Queen.
Queen Margaret refuses to give power to Lorca and is arrested. Sebastian helps Juan, Leporello, and others enter the palace to find the Queen. They fight with the guards, and curtains catch fire. Juan duels with Lorca and kills him with a knife. Margaret goes to Juan, and they kiss. Juan says he must leave because he cannot have the woman he loves. He says she must stay to rule Spain. On the road Juan sees a beautiful woman and follows her.
This classic swashbuckler explores the legendary womanizer
who fights husbands and tyrants to defend women, himself, and
the innocent, reflecting archetypal male fantasies of success
with women and triumph over male competition.