Synopsis
Act I
During his triumphal Asian campaign, Alexander the Great suddenly finds himself in dire danger in the city of Sidrach, which he is the first enemy general ever to invade; he is rescued by his supporters, the most prominent of which is the general Cletus, a Macedonian prince.
Back at Alexander's camp two women fear for the hero's life: Lisaura, a princess of Scythia, and the Persian princess Roxana, who is Alexander's prisoner. They are rivals: both of them love Alexander and are plagued by jealousy, for Alexander, who is affectionate to both of them, does not yet seem to have made up his mind as to which of the two he will choose. The Indian king, Taxiles, who owes Alexander both his throne and his life, reports that Alexander has escaped the danger unharmed. Both of the princesses are overjoyed at this news, much to Taxiles's dismay, for he is in love with the princess Lisaura.
Alexander's fame as an invicible world conqueror has gone to his head. He allows himself to be worshipped in Jupiter's temple as the son of the divine father. The only one who dares stand up to him is the upright Cletus; but at the entreaties of all the others, Alexander is appeased.
Act II
Alexander is still incapable of choosing between the two princesses, who pursue him with their love. Whenever he meets one of them, he seems to nourish her hopes, but the two see through him. Roxana, his beautiful Persian captive, reminds him of his fame and his generosity, and begs him to grant her her freedom. Perhaps she can win him in this way. Alexander fears that he will lose Roxana and only consents with misgivings to her freedom.
General Leonatus and his friends are appalled at Alexander's inordinate arrogance. They resolve to remove the tyrant.
In his quarters, Alexander announces to his assembled generals that he intends to divide all of the conquered territories among them. He, the son of Jupiter, is content with his own immortal glory. Once again, the courageous Cletus confronts Alexander. He vehemently disputes the divine origins of the megalomaniac. Enraged, Alexander is on the verge of killing Cletus with his spear, when suddenly, at a pre-arranged sign of the conspirators, the house caves in. No one is injured, including Alexander, who is convinced that his father Jupiter - divine providence! - has saved him from a certain death. He orders the flatterer Cleon to lead Cletus off to captivity.
Roxana has learned of the attempt on Alexander's life. In despair, she weeps for her lover, whom she presumes dead. Alexander overhears her mourning and is deeply moved; he realises how much she loves him and makes up his mind for her. The conspirator Leonatus rushes in breathless, purporting to have learned that the vanquished peoples are staging an uprising. Alexander wants to return to his army and is forced to leave Roxana behind in a state of renewed uncertainty.
Act III
Leonatus succeeds in freeing the honourable Cletus and imprisoning this jailer Cleon; however, the latter is once again liberated by his followers. The conspirators now intend to defeat Alexander in open battle, with the help of Macedonians who are loyal to them.
Alexander has yet another interview with Lisaura. By means of flattery, and no lack of ingenuity, he explains to her that he must renounce her love to clear the way for the Indian king Taxiles, his dearest friend, who is himself enamoured of the Scythian princess. Taxiles is delighted at Alexander's decision.
In the meanwhile, the conspirators have assembled their forces for battle. Taxiles, with his troops, supports Alexander, and the conspirators are defeated. They all plead with the great Alexander for mercy, which is magnanimously granted.