ACT I   Castle Gesualdo, October 1590

Maria Gesualdo and her secret lover Fabrizio begin a night of carnal delights, each expressing their desires for each other. Maria uses Fabrizio as an outlet for her increasing sorrow over her husband, Carlo. After the lovers fall asleep, a brokenhearted Carlo Gesualdo sneaks into the room seething. Carlo calls in his guards to drag Fabrizio away. After a heated back and forth, Carlo stabs Maria. Anna, her most trusted servant, rushes in to help Maria, but is stabbed to death by a still enraged Carlo. In his delirious state, he calls Fabrizio back to the room. When Fabrizio arrives, Carlo kills him instantly and walks out of the room disgusted.

ACT II   Castle Gesualdo, decades later

After leaving Castle Gesualdo, Carlo and his new wife, Leonora, return. Through the years, Carlo has deteriorated mentally and physically, and this change puts Leonora in a desperate state. After receiving a letter of condolence from her cousin, Leonora begs Carlo to move away to her brother’s home. Carlo, seeing the request as a threat, quickly forbids the move and storms out of the room.

Carlo returns to writing his madrigal. The ghost of Maria returns and subtly torments Carlo. Carlo forces Leonora to listen to his madrigal as he describes his motivations for the piece. A little later, as he is being carried to see Leonora, Carlo is also led by the ghosts of Maria and Fabrizio. The pressure keeps building until Carlo figures out the ending of the madrigal. Suddenly, the ghosts of Maria and Fabrizio are gone and he gains a sense of freedom. He happily takes a drink of the wine that Leonora and Artemisia have offered and releases Leonora to her own will.