The action takes place in Vienna in November 1823, and Salieri's memoirs relate to the decade 1781-1791.

On the front stage in an wheelchair, an old man sits with his back to the audience. The citizens of Vienna repeat each other's last gossip: Salieri is a killer! Their whisper sounds louder. Thirty-two years have passed since the death of Mozart, why did Salieri talk about this right now? Nobody believes Salieri: he is already old and, truly, has survived from the mind. Salieri gets up from his chair, looks into the auditorium. He encourages distant descendants to become his confessors. He says that his whole life was sweet, and asks not to judge him too harshly for this. In addition, he dreamed of fame. He wanted to become famous by composing music. Music is a gift of God, and Salieri prayed to God to make him a great composer, and in return promised to lead a righteous life, to help his neighbors and to the end of his days glorify the Lord in his creations. God heard his prayer, and the next day a friend of their family took young Salieri to Vienna and paid for his music lessons. Soon Salieri was introduced to the emperor, and His Majesty favored the gifted young man. Salieri was glad that his deal with God had taken place. But in the same year that Salieri left Italy, ten-year-old genius Wolfgang Amadeus Mozart appeared in Europe. Salieri invites the public to watch a play entitled "The Death of Mozart, or Am I Guilty." This is his latest work on distant descendants. Salieri throws off his old robe, straightens up and appears before us as a young man in a full dress of the eighties of the eighteenth century. Sounds string quartet Salieri.

1781 Salieri is thirty-one years old, he is a famous composer, he is known at court. He is in love with his student Katarina Cavalieri, but remains faithful to his wife, remembering the vow given to God. Salieri dreams of becoming an over-kapellmeister. Suddenly he learns that Mozart is coming to Vienna. The director of the Imperial Opera, Count Orsini-Rosenberg, receives an order to order Mozart a comic opera in German - the emperor wants to create a national opera. Salieri is alarmed: it seems that the dominance of Italian music is coming to an end. Salieri wants to see Mozart. At evening, with Baroness Waldstaten, he retires to the library to calmly eat sweets, but there suddenly runs in Constance Weber, depicting a mouse, and behind it - Mozart, depicting a cat. Not noticing Salieri, Mozart throws Constance to the floor, rudely jokes with her and, even making her an offer, cannot resist obscene gestures and words. Salieri is shocked by Mozart's vulgarity. But when the concert begins and Salieri hears his music, he realizes that Mozart is a genius. It seems to him that in the Serenade of Mozart he hears the voice of God. Salieri plunges into the work, begging the Lord to inspire his voice in him. He jealously follows the progress of Mozart, but the six sonatas composed in Munich, and the Paris Symphony, and the Great Litany in E flat leave him indifferent. He rejoices that the serenade was a fortunate fortune that could fall to any musician. In the Schönbrunn Palace, Salieri asks Emperor Joseph II for permission to play a welcome march in honor of Mozart. Sounds march. The emperor represents the musicians to each other. Mozart says he has already written the first act of an ordered comic opera. Its action takes place in sera, but the opera is about love and there is nothing obscene in it. The main part will be sung by Katharina Cavalieri, Salieri's favorite student. Mozart thanks Salieri for the welcome march and repeats it as a keepsake, then plays with variations, gradually groping for the theme of the famous march from “Figaro's Wedding” - “Frisky, curly, in love boy”. He rejoices in his improvisation, completely not noticing what an insult Salieri inflicts. Salieri wants to write a tragic opera and shame Mozart. “Abduction from seraglio” does not make much impression on Salieri. Hearing the singing of Katarina, he immediately realizes that Mozart has struck up an affair with her, and is suffering from jealousy. The emperor restrainedly applauds: in his opinion, this opera has “too many notes”. Mozart objects: notes as much as necessary - exactly seven, no more and no less. Mozart represents Salieri, whom he considers a friend, his bride - Constance Weber. Salieri wants to take revenge on Mozart for seducing Katarina, and rob him of Constance.

Mozart marries Constance, but he lives tight: Mozart has few disciples, and he made a lot of enemies by his intransigence. He openly opposes the dominance of Italian music, scolding Salieri’s opera “The Chimney Sweep” with the last words, calls the emperor a mean Kaiser, rudely makes fun of courtiers who may be useful to him. Princess Elizabeth needs a music teacher, but no one wants to please Mozart. Having met Salieri at a ball at the baroness Waldstaten, Constance asks him to help Mozart get the desired place. Salieri invites her to talk. He also wants to see Mozart’s scores to make sure of his talent. When Constance secretly comes from her husband, Salieri declares that he is ready to put in a word for Mozart in exchange for her favor. Constance leaves. Salieri understands his baseness, but blames Mozart for everything: it was Mozart who brought the “noble Salieri” to such vileness. He plunges into reading scores. The 29th symphony in A major is heard. Salieri sees that Mozart’s rough sketches are completely clean, almost without blots: Mozart simply writes the music that sounds in his head in an already finished, perfect form. The theme “Kegue” from Mass to C minor is heard louder and louder. Salieri is slain. He rebels against God, whose favorite - Amadei - is Mozart. Why is Mozart so honored? And Salieri's only reward for a righteous life and hard work is that he alone clearly sees in Mozart the embodiment of God. Salieri defies God, from now on he will fight with all his might, and Mozart will become his battlefield.

Suddenly Constance returns. She is ready to surrender to Salieri, but he does not give free rein to his lust: after all, he does not fight with Mozart, but with the Lord God, who loved him so much. The next day, Salieri seduces Katarina Cavalieri, thereby violating the vow of chastity. Then he leaves all charitable committees, breaking his oath of help to his neighbors. He recommends the emperor as a music teacher for Princess Elizabeth a very mediocre musician. When asked by the emperor about Mozart Salieri, he answers that Mozart’s immorality is such that he cannot be allowed to come close to young girls. The simple-minded Mozart is unaware of Salieri’s intrigues and continues to consider him his friend. Salieri's affairs go uphill: in 1784 and in 1785. the public loves him more than Mozart, although it was during these years that Mozart wrote his best piano concerts and string quartets. The audience applauds Mozart, but immediately forgets his music, and only Salieri and a few other initiates know the true value of his creations.

Meanwhile, Salieri’s operas are staged everywhere and are liked by everyone: both Semiramis and Danaids have won resounding success. Mozart writes The Marriage of Figaro. Baron van Sviten, prefect of the Imperial Library, is shocked by the vulgar plot: the opera should exalt and perpetuate the exploits of the gods and heroes. Mozart explains to him that he wants to write about real people and about real life events. He wants the bedroom to lie on the floor, sheets keep the warmth of the female body, and under the bed there is a night pot. He says that all serious operas of the XVIII century. terribly boring. He wants to merge the voices of his contemporaries and turn them to God. He is sure that the Lord hears the world: millions of sounds arising on the earth ascend to him and, merging in his ears, become music unknown to us. Before the premiere of “The Weddings of Figaro,” the director of the Imperial Opera, Count Orsini-Rosenberg, having looked at the score, tells Mozart that the emperor forbade the use of ballet in operas. Mozart argues: the emperor banned false ballets, like the French, and not dances, which are important for the development of the plot. Rosenberg pulls dance sheets from the score. Mozart is furious: two days later the premiere, and a plot was plotted against him. He scolds the courtiers with the last words. He wants to invite the emperor himself to a rehearsal. Salieri promises to help him, but does nothing. Nevertheless, the emperor comes to rehearsal. Mozart, thinking that this is the merit of Salieri, expresses his gratitude to him. During the performance, dances are performed without musical accompaniment. The emperor is at a loss. Mozart explains what the matter is, and the emperor gives the order to restore the music. Premiere of the opera “The Wedding of Figaro”. Salieri is deeply excited by the music, but the emperor yawns, and the public accepts her restrainedly. Mozart is upset, he considers his opera a masterpiece and is upset by the cold welcome. Salieri comforts him. Mozart would like to go to London, but he has no money. The father refuses to help him, he cannot forgive his son that he turned out to be more talented than him.

Mozart receives news of his father’s death and reproaches himself for his disrespectful attitude towards him, Salieri explains to the audience that this is how the vengeful ghost of his father appeared in the opera Don Giovanni. Salieri decides to resort to the last resort: to starve Mozart, to starve the divine out of his flesh by hunger. He advises the emperor, who decided after the death of Gluck to give Mozart the place of the imperial and royal chamber musician, to put him a salary ten times less than Gluck received. Mozart is offended: you cannot feed such a salary and a mouse. Mozart receives an offer to write an opera for ordinary Germans. It occurs to him to reflect the ideals of Masons in popular music. Salieri says it would be nice to show the Masons themselves on stage. Mozart understands that this is impossible: their rituals are kept secret, but he thinks that if you change them a little, then this can serve to preach brotherly love. Salieri approves of his plan, knowing full well that this will arouse the wrath of the Masons.

Mozart lives in poverty. He often sees a ghost in gray. Constance believes that he is not in himself, and leaves. Mozart tells Salieri that a masked man came to him, like two drops looking like a ghost from his nightmares, and ordered him a Requiem. Mozart has finished work on The Magic Flute and invites Salieri to the premiere in a modest country theater, where there will be no courtiers. Salieri is shocked by the music. The audience applauds, but van Sviten makes his way through the crowd to the composer, he accuses Mozart of betraying the Order. From now on, Masons refuse to take part in Mozart, influential people cease relations with him, Schikaneder, who ordered him the “Magic Flute”, does not pay his share of the fees. Mozart works like a man possessed, waiting for the masked man to order the Requiem. Salieri admits to the audience that he obtained a gray cloak and mask and walks under the windows of Mozart every night to announce the approach of his death. On the last day, Salieri extends his arms to him and calls for him, like a ghost from his dreams. Mozart, having gathered the rest of his strength, opens the window and pronounces the words of the hero of the opera Don Juan inviting the statue to dinner. The passage from the overture to the opera Don Juan sounds. Salieri climbs the stairs and enters Mozart. Mozart says he hasn’t finished the Requiem and asks on his knees to extend the period for a month. Salieri rips off his mask and drops his cloak. Mozart laughs piercingly in a fit of irresistible horror. But after confusion, enlightenment comes: he suddenly realizes that Salieri is to blame for all his misfortunes.

Salieri confesses to his atrocities. He calls himself the murderer of Mozart. He explains to the audience that his confession so easily fell off his tongue because it was true: he really poisoned Mozart, but not with arsenic, but with everything that the audience saw here. Salieri leaves, Constance returns. She puts Mozart to bed, covers with a shawl, trying to calm. It sounds the seventh part of the Requiem - "Lacrimosa." Constance talks to Mozart and suddenly realizes that he is dead. Music breaks off. Salieri says that Mozart was buried in a common grave, with twenty other dead. Then it turned out that the masked man who ordered Mozart Requiem did not see the composer. He was a lackey of a certain Count Walzeg, who secretly ordered Mozart to compose an essay in order to pass him off as his own. After the death of Mozart, Requiem was performed as the work of Count Walzeg, and Salieri was the conductor. Only many years later, Salieri realized what the punishment of the Lord was. Salieri was universally respected and bathed in the rays of glory - and all this thanks to compositions that were not worth a penny. For thirty years he listened to praises from the lips of people who did not understand anything in music. And finally, Mozart’s music was appreciated, and his music was completely forgotten.

Salieri puts on his old bathrobe again and sits in a wheelchair. 1823 Salieri cannot put up with obscurity. He himself is spreading a rumor that he killed Mozart. The louder the glory of Mozart will be, the stronger will be his shame, so Salieri will still gain immortality and the Lord will not be able to prevent this. Salieri is trying to commit suicide, but unsuccessfully. In a notebook where visitors write to deaf Beethoven about the news, there is a note: “Salieri is completely crazy. He continues to insist that he is to blame for the death of Mozart and that it was he who poisoned him. ” The newspaper German Music News in May 1825 also reports on the madness of old Salieri, who blames himself for Mozart’s early death, which no one believes.

Salieri gets up from his chair and, looking into the auditorium, absolves sins of the mediocrity of all time. The last four bars of Mozart’s mourning march sound.