Setting: During the first Crusade
Goffredo, helped by his brother Eustazio, is leading the Crusader army in its siege of Jerusalem. Goffredo’s daughter Almirena is loved by the knight Rinaldo. Goffredo tells Rinaldo that he may marry his daughter if he is victorious in battle. A herald announces the approach of Argante, general of the enemy Saracen army. Argante requests a three-day truce, to which Goffredo assents. Alone, Argante waits for his lover Armida, the powerful sorceress and Saracen Queen. She appears and informs Argante that their only chance of victory lies in depriving the Christian forces of Rinaldo’s support. She herself is prepared to undertake this task.
Rinaldo and Almirena reaffirm their love. Suddenly, Armida and her forces attack them and abduct Almirena. Goffredo and Eustazio arrive. When the distraught Rinaldo tells them what has happened, Eustazio suggests that the Christian Magus will be able to help them. Rinaldo leads them all in their mission to rescue Almirena.
Near a lake, Goffredo, Eustazio and Rinaldo are struggling to find the Christian Magus, when suddenly a beautiful woman appears in a boat. She promises Rinaldo that she will lead him to Almirena. To his companions’ dismay, Rinaldo impulsively jumps on board, and the boat vanishes.
Almirena is now Armida’s captive. She is guarded by Argante, who confesses that he has fallen in love with her. He promises that he will defy Armida and free Almirena if she returns his love, but she rejects him.
Rinaldo, now also a captive, is brought before Armida. He angrily demands that Almirena be set free. Against her will, Armida finds herself falling in love with her enemy. She attempts to seduce him by magically transforming herself into Almirena. Rinaldo, suspecting trickery, rejects her.
Argante now appears and, mistaking the transformed Armida for Almirena, repeats his earlier declarations of love. Armida, outraged by his infidelity, vows vengeance and departs in fury.
Goffredo and Eustazio finally find the Christian Magus, who gives them the magic powers they need to enter Armida’s palace unharmed.
Armida is about to kill Almirena. Rinaldo, still a prisoner, is powerless to prevent her, when suddenly Goffredo and Eustazio come to the captives’ aid. Goffredo, Almirena and Rinaldo rejoice at being finally reunited.
Argante and Armida, now reconciled, prepare their troops. Goffredo’s army also advances, led by Rinaldo, and the battle commences. The Crusaders are victorious. Rinaldo and Almirena celebrate their love, while Armida and Argante accept their defeat. Goffredo forgives the enemy and sets them free, as they all join in a chorus of reconciliation.
Words: George Hall