Longtime allies Rome and Alba went to war with each other. Until now, there have been only minor skirmishes between the enemy armies, but now that the Albanian army is standing at the walls of Rome, a decisive battle must be fought.

The heart of Sabina, the wife of the noble Roman Horace, is filled with confusion and sorrow: now in her fierce battle either her native Alba or Rome, who became her second homeland, will be defeated. Not only is the idea of ​​defeating either side equally sad for Sabina, according to the evil will of fate in this battle, the most dear to her should draw swords against each other - her husband Horace and her three brothers, Albanians of Curia.

Horace's sister, Camilla, also curses evil rock, who has reduced two friendly cities in mortal enmity, and does not consider her position easier than that of Sabina, although her confidant friend Julia repeats it with her and Sabina. Julia is convinced that Camille had to wholeheartedly root for Rome, since only her birth and family ties bind him, the vow of fidelity with which Camilla exchanged with her fiancé Albanian Curiazius is nothing when the honor and prosperity of the motherland are put on the other side of the scale.

Worn out by the excitement about the fate of her native city and her bridegroom, Camilla turned to the Greek soothsayer, and he predicted to her that the dispute between Alba and Rome would end in peace the next day, and that she would unite with Curiacy so that she would never be separated again. The dream that Camille had that night dispelled the sweet prediction deception: in a dream she saw a brutal massacre and piles of dead bodies.

When suddenly a lively unscathed Curation appeared before Camilla, the girl decided that for the sake of love for her, the noble Albanian had given up his duty to his homeland, and in no way condemned the lover.

But it turns out that this is not so: when the rati came together for the battle, the leader of the Albanians turned to the Roman king Tullus with the words that fratricide should be avoided, because the Romans and Albanians belong to the same people and are connected by many kindred ties; he proposed to resolve the dispute by a fight of three fighters from each army on the condition that the city whose soldiers were defeated would become a subject of the victorious city. The Romans gladly accepted the offer of the Albanian leader.

At the choice of the Romans, the three brothers Horace have to fight for the honor of their hometown. Curation and envies the great fate of the Horats - to glorify the homeland or lay down their heads for it - and regrets that at any outcome of the fight he will have to mourn either the humiliated Alba or the dead friends. Horace, the embodiment of Roman virtues, it is not clear how you can grieve over who accepted death in the glory of his native country.

Behind such friends' speeches, an Albanian warrior catches up, bringing the news that Alba has chosen the three brothers Kuriatsiev as her defenders. Curation is proud that it was he and his brothers who fell for the choice of compatriots, but at the same time he would like to avoid this new blow of fate - the need to fight with his sister's husband and brother of the bride. Horace, on the other hand, warmly welcomes the choice of the Albanians, who intended for him an even more elevated lot: it is a great honor to fight for the fatherland, but at the same time to overcome the bonds of blood and human affection - few people managed to gain such perfect fame.

Camilla is doing her best to dissuade Curation to engage in a fratricidal duel, conjures him with the name of their love and almost succeeds, but the noble Albanian still finds the strength not to change his duty for the sake of love.

Sabina, unlike a relative, does not think to dissuade her brother and husband from the duel, but only wants this duel not to become fratricidal - for this she must die, and with her death the family ties that bind Horatiev and Kuriatsiev will break.

The appearance of the old Horace ends the conversations of the heroes with women. The honored patrician commands his son and son-in-law, relying on the court of the gods, to rush to the performance of a high duty.

Sabina tries to overcome spiritual grief, convincing herself that, no matter who falls in the battle, the main thing is not who brought him death, but in the name of what; she inspires herself that she will certainly remain a faithful sister if the brother kills her husband, or a loving wife - if the husband hits the brother. But all is in vain: Sabina confesses again and again that in the winner she will first of all see the killer of a person dear to her.

Sabina’s woeful thoughts are interrupted by Julia, who brought her news from the battlefield: barely six fighters came out to meet each other, a murmur ran through both armies: both the Romans and Albanians were outraged by the decision of their leaders, who had sent Horace and the Curia to a criminal fratricidal duel. King Tull heeded the voice of the people and announced that sacrifices should be made in order to find out from the insides of the animals whether the gods were pleasing or not, the choice of fighters.

In the hearts of Sabina and Camille, hope re-settles, but not for long - old Horace tells them that, by the will of the gods, their brothers entered into battle among themselves. Seeing the grief that this news plunged women into, and wanting to strengthen their hearts, the father of the heroes speaks about the greatness of the lot of his sons, performing feats for the glory of Rome; the Romans - Camille by birth, Sabina by virtue of marriage, both of them at this moment should only think about the triumph of their homeland ...

Presenting herself again to her friends, Julia tells them that the two sons of old Horace fell from the swords of the Albanians, while the third, the husband of Sabina, flees; Julia did not wait for the outcome of the fight, because it is obvious.

The story of Julia strikes old Horace in the heart. Paying tribute to the two gloriously lost defenders of Rome, he swears that the third son, whose cowardice indelibly disgraced covered the honest name of Horatiev, would die by his own hand. No matter how Sabin and Camilla ask him to moderate his anger, the old patrician is implacable.

To old Horace, a messenger from the tsar comes Valery, a noble young man whose love was rejected by Camille. He makes a speech about the surviving Horace and, to his surprise, hears terrible curses from the old man against the one who saved Rome from shame. Only with difficulty interrupting the bitter outpourings of the patrician, Valery talks about something that Julia did not see prematurely leaving the city wall: Horace’s flight was not a manifestation of cowardice, but a military ploy - fleeing the wounded and tired Curiazius, Horace thus separated them and fought them off each in turn, one on one, until all three fell from his sword.

Old Horace triumphs, he is full of pride for his sons - both survivors and those who have laid their heads on the battlefield. Camille, struck by the news of the death of his beloved, the father consoles, appealing to the reason and fortitude that always adorned the Romans.

But Camille is inconsolable. And not only is her happiness sacrificed to the greatness of proud Rome, this very Rome requires her to hide her grief and, together with all, rejoice at the victory won at the cost of crime. No, this will not happen, Camilla decides, and, when Horace appears before her, expecting praise from her sister for her deed, brings down a stream of curses on him for killing the groom. Horace could not have imagined that at the time of the triumph of the motherland, one could be killed after the death of her enemy; when Camilla begins to vilify Rome with the last words and call terrible curses on her hometown, his patience comes to an end - with the sword, which shortly before her fiancé was killed, he stabs his sister.

Horace is sure that he did the right thing - Camilla ceased to be a sister to him and the daughter of her father in an instant when she cursed her homeland. Sabina asks her husband to stab her too, for she, contrary to her duty, mourns for the lost brothers, envious of Camilla’s fate, which death saved the hopeless sorrow and connected with her beloved. Horace is a lot of work is not to fulfill the request of the spouse.

Old Horace does not condemn his son for the murder of his sister - having changed Rome by her soul, she deserved to die; but at the same time, by the execution of Camille Horace irrevocably ruined his honor and glory. The son agrees with his father and asks him to pronounce a sentence - no matter what he is, Horace agrees with him in advance.

In order to personally honor the father of the heroes, King Tull arrives at the house of Horatius. He praises the valor of old Horace, whose spirit was not broken by the death of three children, and regrets the villainy that overshadowed the deed of the last of his surviving sons. However, that this atrocity should be punished is out of the question until Valery takes the floor.

Calling on royal justice, Valery speaks of Camille's innocence, which succumbed to a natural outburst of despair and anger, that Horace not only killed a blood relative for no reason, which was terrible in itself, but also abused the will of the gods, blasphemously defiling the glory granted by them.

Horace does not even think of defending himself or making excuses - he asks the king of permission to pierce himself with his own sword, but not to atone for the death of his sister, because she deserved her, but in the name of saving her honor and glory of the savior of Rome.

The wise Tull also listens to Sabina. She asks to execute her, which will mean the execution of Horace, since husband and wife are one; her death - which Sabina seeks as deliverance, unable to love either the killer of her brothers or reject her beloved - will quench the wrath of the gods, while her husband can continue to bring glory to the fatherland.

When all who had something to say spoke out, Tull pronounced his sentence: although Horace committed the atrocity, usually punishable by death, he is one of the few heroes who, on decisive days, serve as a reliable stronghold of their sovereigns; these heroes are not subject to the general law, and therefore Horace will live, and further jealous of the glory of Rome.