Scene 1: A crowd of gypsies, beggars, prostitutes and toreros sings and dances in a tavern on the outskirts of Madrid. Among the revelers is the young painter Francisco Goya, freshly arrived in Madrid from the country. Suddenly a mysterious, discreetly veiled woman enters. Goya, attracted to the woman, boldly introduces himself as Spain's greatest painter and asks if she would pose for him. Amused by Goya's youthful arrogance, she accepts. She identifies herself as a maid in the Alba palace, and invites him to come tomorrow afternoon to paint. Outside the tavern door, Goya watches in horror as Inquisition monks lead a group of accused heretics to trial.
Scene 2: Goya is led to the drawing room of the Alba palace and waits for his model. The doors of the drawing room are suddenly thrown open and the supposed "maid" who in reality is the Duchess of Alba enters. Dona Cayetana (the Duchess of Alba) and her entourage laugh at the trick that has been played on Goya. Goya slowly regains his self-assurance and begins to paint her after they are left alone. Though Cayetana is fascinated by her protegé, she tires of posing and dares Goya to paint the very skin of her face. Half in jest and half seriously Goya approaches her and begins to caress her features with his brushes. As he reaches her mouth, he lets the brushes fall and kisses her passionately.
The Queen Maria Luisa is angry that the Duchess' nightly escapades, insolent manners and new lover have created a scandal. The Queen demands that Prime Minister Godoy get rid of the Duchess, and desires Goya for herself. Godoy and the ineffectual Charles IV try to calm her, telling her that Goya will be presented at the daily reception. Goya, The Duchess and other guests arrive at the reception. After bowing slightly to the Queen, the Duchess ushers in her ladies-in-waiting, who are wearing identical copies of the Queen's own dress. Unable to contain her rage, the Queen has to be led away from the scandalized, but amused court. Cayetana is jubilant, but Godoy chastises her. Goya takes her aside and berates her, but the Duchess strikes back, accusing Goya of being an opportunist and a coward. She tells him that their affair is over. Goya, alone and dismayed, is approached by Charles IV. The King intends to promote him to court painter but warns Goya that he must sever his relationship with the Duchess. As the King continues to talk, Goya begins to lose his hearing, and the room becomes silent. As a single high, ringing note pierces Goya's ears, he cries out in anguish. "Cayetana, Cayetana, even your voice is taken from me," Goya cries, collapsing in despair.
Scene 1: Cayetana, stricken by a mysterious illness, is about to die. Sitting on an armchair and still wearing her famous jewels, she begs Martin Zapater to fetch Goya so that she may give him her favorite ring. The Queen visits the Duchess tells her that she is receiving her just punishment. Cayetana replies that she knows who has poisoned her, and declares that her entire fortune will be left to her servants and adopted child. After Cayetana dies, the Queen takes the diamond necklace and ring from the Duchess' body. She calls in her attendants and announces that the Duchess has kindly left her jewels to her. Goya rushes into the room and notices the Queen wearing Cayetana's ring. Left alone, he curses himself for failing to save Cayetana.
Scene 2: In the painter's studio, many years later, Goya is now both deaf and blind in his final hours. As he fitfully sleeps in his armchair, Goya is haunted by a series of visions. He is tormented by his lack of courage during the war and by his sense of guilt at having abandoned his wife, Pepa. He calls for help and the beautiful Cayetana appears to him. She tells him that he must not feel guilty. With his brush, she says, he has fought more courageously than any other soldier; he has loved more deeply and more passionately than any lover; he has been more compassionate than any priest. He surely deserves the heavenly peace that death will now bring to him.