Under the leadership of their King Amonasro, the Ethiopians are again threatening the kingdom of Egypt. At the advice of the goddess Isis, Radames is to be placed in command of the Egyptian army raised against the Ethiopians (introduction).
Radames dreams of honour and fame – and of Aida, an Ethiopian slave to Amneris, the Pharaoh’s daughter. A deep but secret love binds Radames to Aida (Radames’ romanza). However, Amneris is also passionately in love with the bold young warrior (duet: Amneris-Radames). Sudden suspicion is kindled in her breast when she notices the looks that the lovers exchange (trio: Aida, Amneris and Radames).
With much rejoicing and ceremony, Radames is appointed commander of the army by the Pharaoh (scene and ensemble). Aida is despondent: her beloved Radames is about to fight against her own people, and (nobody at the Egyptian court knows this) against her father Amonasro (scene and romanza of Aida). The priests and priestesses call on the god Ptàh to support the Egyptians in their struggle against the Ethiopians. Radames receives the holy sword of victory from Ramfis, the high priest (temple scene and Act 1 finale).
The Egyptian army has defeated the enemy. Amneris is being dressed by her slaves for the celebration to mark the victory. Longingly she awaits Radames, whom she so loves (introduction). But suddenly she is again tormented by doubt. Is Aida really her rival for his love? She must know for certain. She tricks Aida into revealing her love for Radames (scene and duet Aida- Amneris).
The victorious Radames is given a triumphant welcome. Aida sees her father in the procession of Ethiopian captives. However, Amonasro does not reveal his identity, saying that the Ethiopian king has been slain in battle and begging for mercy for his
fellow captives. Radames supports his request in spite of Ramfis’ warning. The captives are released. Only Aida and her father are to remain as hostages at the Egyptian court. In gratitude for his courageous efforts for the fatherland, the Pharaoh offers Radames the hand of his daughter Amneris in marriage and the succession to the throne. The people rejoice, and the rapturous Amneris is convinced that her dreams have come true (Act 2 finale).
Ramfis leads Amneris into the temple of Isis to spend the night in prayer prior to her marriage to Radames (introduction and prayer). Aida awaits Radames (Aida’s romanza). Amonasro, who has noticed his daughter’s affection for the Egyptian commander, has followed her. Conjuring up visions of the suffering of her people, he persuades Aida to induce Radames to reveal the Egyptians’ plans for attacking the Ethiopian army, which has now received reinforcements. In despair, Aida agrees to comply with his wish.
Amonasro goes into hiding (duet Aida-Amonasro). Aida manages to persuade Radames to flee with her and to tell her a path that will be safe from the Egyptian army (duet Aida-Radames). However, by doing so Radames reveals the Egyptian plan of deployment for the forthcoming battle. Triumphant, Amonasro emerges from his hiding-place and discloses his identity as king of the Ethiopians. Radames, realizing the extent of his folly, gives himself up to the guards. Amonasro and Aida flee (scene and Act 3 finale).
Radames is accused of high treason and is to be condemned to death. Amneris still loves him, and tries to save him from the fate that awaits him by persuading him to renounce his love for Aida. However, life has no meaning for Radames without Aida. He rejects Amneris’ proposition (scene and duet: Amneris-Radames) and accepts the priests’ judgement in silence: he is to be buried alive (judgement scene).
Radames awaits the end in an underground vault. Suddenly he becomes aware that he is not alone. Aida has managed to steal in unnoticed to die with her beloved Radames. The couple’s love is perpetuated in death. Amneris prays for eternal peace for Radames (scene, duet Aida-Radames, finale).