FIRTS ACT

Cesare Angelotti, a former consul of the ancient Roman republic and a political prisoner, escapes from prison. He enters the Sant'Andrea della Valle Church and finds the key to his sister Marchesa Attavanti's private chapel, hidden beneath the statue of the Virgin Mary. As he takes the key and conceals himself in the chapel, the Sacristan enters to begin cleaning. Meanwhile, the painter Mario Cavaradossi arrives at the church. While Mario Cavaradossi is working on a painting of Mary Magdalene, the Sacristan notices that the blonde woman in the painting bears a striking resemblance to someone who has been frequenting the church lately. Cavaradossi remarks on the contrast between the beauty of the blonde woman in the painting and the dark allure of his lover, Floria Tosca. After the Sacristan departs, Angelotti emerges from his hiding place, embraces his friend Cavaradossi, whom he knows to be a fellow republican, and urgently informs him that the police chief, Scarpia, is hot on his trail. As night descends, Cavaradossi promises to aid his friend, Angelotti. From outside the church, Tosca's voice reaches them. Cavaradossi hands Angelotti a basket of food and instructs him to conceal himself once more. He then unlocks the door, allowing Tosca to enter. Consumed by jealousy, she interrogates her lover about his actions and the reason for the locked door, suspecting he harbors another lover. After Cavaradossi convinces her, they agree to meet at the painter's villa later that night. Tosca, now fixated on the woman in the painting, asks about her identity and realizes it is Marchesa Attavanti. Cavaradossi reassures her once again, explaining that he merely painted a woman who caught his eye while she was praying, and leaves the church. After Tosca exits, Angelotti asks Cavaradossi if it would be wise to disguise himself in women's clothing prepared by his sister to escape. Cavaradossi gives him the key to his villa and advises him to hide in the dried-up well in the garden. At this moment, the sound of a cannon is heard, indicating that Angelotti's escape has been discovered. Two men rush out of the church.
The Sacristan returns and assembles the monk students in the monastery to announce Napoleon's victory at Marengo. While everyone rejoices, Scarpia, along with his assistant Spoletta and other police officers, enters the church. They harbor suspicions that Angelotti is hiding there. When they interrogate the Sacristan, they learn that the food basket has been prepared for Cavaradossi. Thus, they realize that the collaborator of Angelotti is the painter Cavaradossi.
Tosca returns to the church to reunite with her lover. However, Scarpia, with a cunning plan, reveals Attavanti's fan to Tosca and falsely informs her that Cavaradossi has been unfaithful. Enraged, Tosca swiftly departs to confront the two lovers at Cavaradossi's villa. Meanwhile, Scarpia instructs Spoletta to tail Tosca, ensuring they will eventually locate both Cavaradossi and Angelotti. As the church service continues, Scarpia plots to possess Tosca and orchestrate Cavaradossi's execution.

SECOND ACT

In his room at the Palazzo Farnese, Scarpia is enjoying dinner. He dispatches a note to Tosca, summoning her to his quarters. His agent, Spoletta, enters and informs him that Angelotti remains elusive, but they have apprehended Cavaradossi. Scarpia commences the interrogation of Cavaradossi. The young man vehemently denies any connection to Angelotti, while Tosca's cantata drifts faintly in the background. As the cantata concludes, Cavaradossi whispers to Tosca, who is secretly ushered into Scarpia's chamber, instructing her to remain silent. He is then led away to another room.
Scarpia then turns to Tosca and explains that she must reveal Angelotti's hiding place to prevent her lover from being tortured. Initially denying knowledge of anything, Tosca eventually succumbs to her lover's screams and reveals that Angelotti is hidden in the garden well. Scarpia orders the torture to stop and commands that Cavaradossi be brought into the room. Upon learning that Cavaradossi has divulged his secret, Scarpia curses Tosca. However, news arrives that the tides of war have abruptly shifted, with the French advancing on Rome. Cavaradossi, facing Scarpia, proclaims the imminent end of the oppressive regime and the arrival of freedom. These words prove sufficient for Scarpia to pronounce Cavaradossi's arrest and impending execution. The police promptly escort him from the room to the dungeon. Alone with Tosca, Scarpia extends an offer; in exchange for herself, Cavaradossi will be granted freedom. Initially resistant, Tosca's horror intensifies upon hearing the approaching execution squad. Spoletta returns and delivers the news that Angelotti has taken his own life upon discovery. The stage is set for Cavaradossi's imminent execution. Tosca ultimately accepts Scarpia's proposition.
Scarpia instructs Spoletta to orchestrate a deceptive execution, akin to the ruse employed with Count Palmieri. As Spoletta departs, Tosca implores him to draft a safe-conduct document for their escape. Meanwhile, Scarpia pens the requested document, and Tosca's gaze falls upon a knife resting on the table. As Scarpia draws near to embrace her, Tosca drives the blade into his chest, ending the life of him. She secures the safe-conduct pass and, before departing, places candles and a cross on either side of Scarpia's lifeless form.

THIRD ACT

On the terrace of Sant'Angelo Castle, guards maintain their vigilance. In the distance, the melancholic song of a shepherd drifts through the air. The soldiers escort Cavaradossi, informing him that his execution is imminent, scheduled within the hour. Desperate, Cavaradossi bribes one of the soldiers, offering his ring in exchange for delivering a letter to his beloved, Tosca.
Meanwhile, Tosca reflects on her past, lost in contemplation. Suddenly, her lover rushes to her side, embracing her. He reveals a critical document; proof that he murdered Scarpia and that his impending execution is but a theatrical charade. Cavaradossi will feign death, allowing them to escape undetected before Tosca's own crime is exposed. Together, they ponder the uncertain life awaiting them.
As the fateful moment arrives, soldiers lead Cavaradossi to the execution site. Tosca watches in anguish as the events unfold. The guns discharge, and Cavaradossi crumples to the ground. When the soldiers depart, Tosca desperately tries to revive her fallen lover, but it is too late-Cavaradossi lies dead.
Meanwhile, Spoletta is coming to apprehend Tosca as Scarpia's murder has been discovered. Defiant, Tosca ascends to the castle's pinnacle, declaring that she and Scarpia will face divine judgment. With unwavering resolve, she leaps to her own demise.