As it happened, the Princess Amneris had also arranged to visit the Temple of Isis that night, in order to offer prayers and incense to the goddess on this the last evening of her maidenhood, in accordance with an ancient custom; and attended by women-slaves and guards, she arrived soon after darkness had set in, and was immediately conducted by Ramphis, the High Priest, into the Temple, where she began her vigil.
No sooner had the Princess and her party retired within the sacred building, than Aïda, alone and unattended, drew near, trembling with fear; and almost immediately she was joined by her father, who had awaited her arrival in a hiding-place close by. Quickly reassuring the frightened maiden, Amonasro informed her of the service he wished her to do for him; and after declaring that his reassembled forces were already prepared and waiting for battle, reminding her also of the wretched condition of their people, he entreated her to discover from her lover by what path the Egyptians intended to surprise their enemies, a fact which, in the hands of the Ethiopians, meant success to their enterprise.
At first, Aïda refused indignantly to ask her lover to be disloyal to the arms he bore; but upon Amonasro declaring reproachfully and angrily that he would no longer regard her as his daughter if she thus refused to help her country, she reluctantly promised to seek the information needed. Amonasro now retired to his hiding-place; and as he departed, Radames came up to the meeting-place, and clasped Aïda in his arms in a passionate embrace.
When the first joy of meeting was over, Aïda asked her lover to tell her of his plans, for since his nuptials with the Princess were now so near at hand, it seemed well-nigh impossible for him to avoid the step, which was the express command of the King and the wish of the people; and the hopelessness of the situation made her have misgivings whether he would care to make so great a sacrifice for her sake. Radames, however, declared that not all the wealth of Egypt could make up to him for the loss of Aïda's love; and, with eager enthusiasm, he declared to her that early next morning he would join the Egyptian forces now under arms, and after leading them once more to victory, he would return triumphant to the city, and then, telling the King of his love for the Ethiopian maid, beseech him of his mercy to grant him her hand in marriage as a reward.
But Aïda was not satisfied with this, knowing that the rage and jealousy of Amneris would never permit them to marry; and she cried eagerly:
"Nay, there is but one course, my beloved! Let us fly to-night, and in a far-away land, where we are not known, we may pass our life in perfect joy together!"
Then, seeing that Radames hesitated at this suggestion, which meant his resignation of all the glory and renown he had won, she thrust him from her, exclaiming passionately: "Ah, then, you love me not! Return to the Princess of Egypt, and in the enjoyment of her embraces forget poor Aïda, who would now gladly seek death!"
This was more than Radames could endure; and, clasping Aïda in his arms once again, he declared that they would indeed fly that night, since her love was more to him than anything else the world could offer.
Intoxicated with the intensity of their passion, the lovers prepared to carry out their resolve at once; but, as they were about to depart, Aïda, remembering with a pang her father's command, said in a trembling voice: "How shall we escape being seen by the Egyptian soldiers?"
"All will be well," returned Radames reassuringly, "if we avoid the Pass of Napata, where they lie hidden!"