THE action takes place at and around Oxidraca, an Indian city on the Ganges (but unknown to classical geography). The Argument points out that Alexander the Great's almost single-handed capture of the city, his quarrel with Clito, whom he kills for deriding his claim to be the son of Jupiter, and his passionate love for Rossane ‘are Facts deduced from the History of those Times. But the Amours of Lisaura Scythian Princess with Alexander, as those of Taxilis the Indian King with Lisaura, and the rest, are entirely fabulous.’

Act I begins with a spectacular tour de force: Alessandro, proclaiming himself the son of Jove, by the Means of a Scaling Engine, mounts the Walls of Oxidraca … The Besieg’d fly at the Approach of Alexander … He throws himself within the Wall: The Besieged rally thither again, and repulse the Besiegers back with their Scaling-Machine. Leonatus, a Macedonian captain arrives with other Soldiers, and with a Batt’ring Ram to demolish the Wall … The Wall tumbles; and Alexander is seen among a Heap of slaughter’d Enemies, and defending himself against others, who are all put to flight by Leonatus, and his Macedonians (see Plate 1a and b). Leonato remonstrates with Alessandro for risking his precious life by rushing ahead to ‘gain the Palm alone’. Alessandro prefers a short life with fame and honour. Exeunt all re-entering thro’ the Breach. In an Encampment Rossane and Lisaura, issuing forth, each from her Pavilion, within Sight of the ruin’d Wall. Each loves Alessandro and fears for his fate. Tassile informs them that Oxidraca has fallen and Alessandro is safe. Lisaura would be delighted but for jealousy of her rival. Rossane (Alessandro's captive) feels much the same, and resolves to exercise all her charms on the victor. Tassile is grateful to Alessandro for restoring his throne but resents him as a rival for Lisaura's love and prays that he may fall for someone else. In the Breach Alessandro, echoed by Tassile and the three Macedonian captains, Leonato, Cleone and Clito, boasts of his glory and regrets that there are no more worlds to conquer. Cleone flatters him. The ladies enter; he embraces first one, then the other, making both and Tassile jealous. Lisaura resolves to stand it no longer.