On a November night in 1823 a distracted old man offers from his window an appalling confession to the city of Vienna: “Forgive me, Mozart. Forgive your assassin.” Moments later he attempts suicide, and is rushed through the snowy streets to the General Infirmary, a grim building containing all manner of sick and desperate patients. Some weeks afterwards, confined in a private room, the Hospital Chaplain, Father Vogler, visits him. While obviously contemptuous of the priest, the old man is drawn to confess to him. His story, told throughout one night, forms the substance of the film.
The old man is Antonio Salieri, once the most famous musician in Vienna. A small town Italian lad from Legnago, he worked his way up to becoming Court Composer to Emperor Joseph II, brother of Marie Antoinette and lover, in a limited way, of music. All his early life Salieri had been possessed by one driving desire: to serve God through music. As a boy he made a solemn vow to Him in Church, offering his chastity, his unremitting industry, and his deepest humility if God in His turn will grant him musical excellence as a composer, and immortal fame for its exercise.
At first it seems to Salieri that his offer has been accepted. He goes to Vienna and rapidly becomes the most successful musician in that city of musicians and is accepted as Court Composer. Then in 1781 a young man arrives and changes everything forever - WOLFGANG AMADEUS MOZART. Already famous as a prodigy at the age of six, Mozart was toured throughout Europe by his dominating father Leopold, showing off musical tricks for the amusement of the aristocracy. Now at age 26, the young man is far more than a performing monkey. He has become a composer, eager to show off his abilities. Salieri hears that Mozart is to give a concert of his music at the residence of his employer the Archbishop of Salzburg, and hurries there to hear it. That night changes his life.
Before the concert starts the Court Composer strolls through the throng of fashionable guests, striving to guess which one can be Mozart. Trays of pastries being carried by servants to the buffet suddenly distract his eye. He follows them, eager to steal a little private refreshment—he is possessed of an Italian sweet tooth—but instead encounters a giggling couple playing together on the floor like children, and rather dirty-minded children at that.
Concealed from view, he is obliged to listen to an infantile scatological game played by the boy-man who is wildly attracted to the girl-woman. Salieri is scandalized by what he hears - and then astounded as music suddenly sounds from the great salon, and the boy springs up in alarm, cries “My music” and dashes from the room. This is Mozart? This giggling, naughty figure? And worse: the music Salieri hears—an adagio from the Wind Serenade for Thirteen Instruments—is the most beautiful he has ever heard in his life. God is apparently favouring not him, but a sniggering, unattractive little show-off.
From this moment, Salieri’s relations with his God begin to deteriorate. In the ensuing weeks he often meets Mozart, and the young man proceeds to unwittingly insult him in a variety of ways: firstly by sitting at the keyboard and turning the dull March of Welcome Salieri has composed into the brilliant tune later to be made world famous in “The Marriage of Figaro”-- Non Piu Andrai; secondly by seducing Salieri’s prize pupil Katerina Cavalieri, who sings the lead in the opera especially commissioned by a benevolent Emperor Joseph II. When his Majesty decides to show an additional mark of favour to Mozart by proposing him as a teacher of music to his royal niece, Salieri decides to block the appointment. Constanze, Wolfgang’s wife, appears secretly at Salieri’s house to plead for her husband, bearing with her manuscripts of his music as evidence of his ability. Salieri studies them as she waits. The manuscripts form an incredible miscellany of work—the slow movement of the Flute and Harp Concerto; the last movement of the Concerto for Two Pianos; the Twenty-ninth Symphony; the Kyrie from the C Minor Mass. Incredibly, these original and first drafts of the music show no corrections of any kind; it is just as if Mozart has taken down dictation from God Salieri reads on, overwhelmed, he is maddened by their perfection. Mozart has been chosen to be His instrument; Salieri must remain forever mediocre, despite his longings to serve. In fury he turns on the Deity. He makes demands of Him: “Why implant the desire to serve and then withhold the talent to do it? Why bestow your divine genius on Mozart, who is neither good nor chaste?” Goodness is nothing in the furnace of art. And for that reason he vows to ruin God’s incarnation—Mozart—as far as he is able.
Relentlessly Salieri plots to destroy Mozart. When “The Marriage of Figaro” comes to be produced, he does everything in his power—largely through the Italian faction at Court—to ruin it. Inevitably Mozart begins to sink into poverty and sickness.
Finally the Court Composer discovers a real weakness in his victim’s character, through which he can destroy him not only economically but also physically and mentally. Mozart’s father Leopold visits Vienna to stay with his son and daughter-in-law, of whom he violently disapproves. The visit—despite attempts to cheer it up with parties and masquerades—is a disastrous failure, and the old man leaves for Salzburg in bitterness. Shortly thereafter he dies. Mozart is badly stricken. Salieri perceives, at a performance of the opera “Don Giovanni” that in the dreadful figure of the accusing statue, Mozart has summoned up his father to accuse him, publicly, on stage. Guilt is deeply ingrained in the son’s soul, ready to be used against him by an enemy. Surprisingly, however, Salieri’s aim is not his immediate destruction.
As the life of Mozart grows more and more desperate, he lapses into sickness and drunkenness and turns from the Court which has turned from him to produce entertainment for ordinary German people in the popular theatre of Emanuel Schikaneder, Salieri, his tormented persecutor, suddenly decides that he wants Mozart alive—at least for the moment. His lust for immortality propels Salieri toward a new and pathetic wickedness. Committed to his war with his Maker, he finally hits on the one stratagem that, in his eyes, could enable him to win he battle for eternal recognition. The old man’s confession climaxes with this stratagem and the inevitable outcome of any such absurd challenge to divinity. God replies to Salieri...in his own way.