Act I
The Pharaoh’s palace received the news, that Ethiopians would threat to attack Egypt. Radames is willing to lead the forces and win, he hints about it to the High Priest. The Pharaoh’s daughter Amneris is in love with Radames. She guessed about his passion to the slave Aida, when she sees him in a strong excitement. Priests hold the rite of passage to consecrate Radames as the Commander.
Act II
Amneris is waiting Radames’ returning – he won the Ethiopians. Suspecting Aida is the rival and trying to learn her feelings to Radames, she tells Aida about his death. A wail of despair reveals Aida…Everything is ready for meeting the winners on the square in Thebes. The triumphant appears with the captured Ethiopians, there is Amonasro (the King of Ethiopia, Aida’s father) among them. Trying to avoid suspicion, he impersonates himself as the Commander and tells, that the King of Ethiopia is died in battle. The captives and slaves are begging for mercy. The Pharaoh frees them, but keeps Amonasro and Aida hostage at the priests’ insistence. The Pharaoh grants Amneris’ hand to Radames.
Act III
Night. The temple. Amneris prepares to the wedding with Radames. Aida waits him on the bank of the Nile to say goodbye forever. Amonasro appears and demands Aida to worm a secret out of Radames: which road will he lead troops against the Ethiopians.
During the date Radames reveals the secret. Amonasro comes out of hiding and confesses, that he is the King of Ethiopia. He proposes to escape in Ethiopia. But Amneris and Ramfis overhear it and dispel the plan. Radames confesses in treason against the fatherland.
Act IV
Amneris wants to save the beloved, begs him to repent, promises Pharaoh’s intercession, freedom, richness and throne. But Radames rejects her feelings. The priests headed by Ramfis pronounce a sentence: for the betrayal Radames will be buried alive. Amneris damns priests’ inhumanity, but they are uncompromising. Dying, Radames hears Aida’s voice. They are leaving life in each other's arms. Poor Amneris will pray for peace to the death.