In the late 1400s, in Moorish-occupied Granada, Spain, Pedro de Rivera, rightful owner of the castle now occupied by the Moorish Caliph who murdered Pedro's parents, plans to reclaim his possessions and secretly enters the castle. He is accompanied by Juan Ponce de León, who intends to steal the "Rose of Granada," a rare gem owned by the Caliph, which supposedly contains a rare essence that ensures eternal youth. Once inside the castle, Pedro and Juan encounter a priest, Father Angélico, who has been a virtual prisoner for twenty years, and Lolita, a fiery swordswoman dressed as a man. She tells them that, having been born into a poor family, she wants to be the richest woman in the world. She has discovered that the Caliph has an alchemist who can turn metals into gold and tells Pedro and Juan that, if they help her to get the formula, she will supply troops to attack the castle. Angélico asks to join their campaign as he wishes to restore a cross to the castle tower. Pedro assures them that, as soon as the Caliph is dead, he will sound a bell which will alert the villagers to attack the castle. Juan is reluctant to have Lolita join them as he fears that she will betray them if captured and tortured. Eventually, however, all four agree to work together to achieve their particular desires and plan to reach the Caliph via the quarters of his niece, Princess Esmé. The Caliph has arranged a marriage for Esmé, and Angélico has been instructed to take a portrait of her future husband, the Caliph of Cordova, whom she has never seen, to her. However, before he does so, he alters the painting so that the face resembles Pedro's. Once in her room, Angélico is able to locate a secret passageway to the Caliph's chambers. Later, all four are captured as they attempt to pass through Esmé's room and are taken to a dungeon. Esmé is puzzled as she realizes that the face in the portrait is that of the man she has just seen arrested. When the Caliph fails to discover who devised the plan, he orders that the prisoners be whipped. Esmé asks to speak with the prisoners alone and tells Angélico that she expects to benefit from her upcoming marriage. However, after Angélico tells her that her betrothed is really old and ugly, Esmé informs her uncle that she will not go through with the marriage. The whipping continues and the rebels are threatened with execution unless they reveal who sent them there. After Sara, Esmé's hand maiden, tells her about the intended execution, Esmé finds a secret passageway to the dungeon where the prisoners are being held, draws a knife on a guard and orders him to release the prisoners. When the captain of the guard finds out that Esmé is responsible for the escape, he goes to her room, but is accidentally killed by his own men as he searches for the passageway. On their way to the Caliph's quarters, Lolita finds the alchemist's laboratory and, at knifepoint, demands the formula. The alchemist swears that there is no formula, that it is a myth, but they struggle and she breaks a bottle over his head. He knocks her out, then collapses and dies. The others find Lolita and, as she recovers, she realizes that she is falling in love with Pedro. After Esmé is captured and tortured, Pedro, Juan, Angélico and Lolita attempt to rescue her, but are foiled by several guards, who involve them in sword fights. Pedro discovers that his opponent is a man who fought alongside Pedro's father, and the man surrenders to him. Although both Angélico and Lolita are injured, all burst into the Caliph's chambers just as he orders Esmé's death. As the priest comforts Esmé, Pedro and the others engage the Caliph and his guards in more sword fights. Pedro mortally wounds the Caliph then rings the castle bell to summon the villagers. Juan asks the dying Caliph about the Rose of Granada, but the secret dies with him. Angélico tells Juan that as the Caliph looked old and cruel, he could not have possessed the secret of eternal youth. Juan is resigned, but still expresses hope that he will find the source somewhere. When Esmé collapes in Pedro's arms, Lolita thinks he has forsaken her, but he soon turns to her and they kiss.