

Constanze returns and demands that Salieri leave immediately. The next morning, Mozart thanks Salieri for his friendship, and Salieri admits that Mozart is the greatest composer he knows. Salieri takes him home and persuades him to continue the Requiem, offering to take the bedridden Mozart's dictation. Mozart's new opera, The Magic Flute, is a great success, but the overworked Mozart collapses during one performance. After arguing with Mozart, Constanze leaves with their young son, Karl. Mozart obliges despite his wife Constanze's insistence that he finish the Requiem. Meanwhile, Mozart's friend Emanuel Schikaneder invites him to write an opera for his theatre. He then plans to kill Mozart once the piece is finished and premiere it at Mozart's funeral, claiming the work as his own.

Salieri recognizes the dead commander in the opera as symbolic of Mozart's father and concocts a scheme he leads Mozart to believe that his father has risen to commission a Requiem. When Mozart is informed that his father has died, he writes Don Giovanni in his grief. When Mozart is summoned to court to explain, he manages to convince the Emperor to allow his opera to premiere, despite Salieri and the advisers' attempts at sabotage. Salieri hires a young girl to pose as Mozart's maid and discovers that Mozart is working on an opera based on the play The Marriage of Figaro, which the Emperor has forbidden. Mozart's alcoholism deteriorates his health, marriage, and reputation at court, even as he continues to produce brilliant work. Salieri renounces God and vows to take revenge on Him by destroying Mozart. Salieri, a devout Catholic, cannot fathom why God would endow such a great gift to Mozart instead of him and concludes that God is using Mozart's talent to mock Salieri's mediocrity. Seven years later, at a reception in honor of Mozart's patron, the Prince-Archbishop of Salzburg, Salieri is shocked to discover that the transcendentally talented Mozart is obscene and immature. By 1774, Salieri has become court composer to Emperor Joseph II in Vienna. Soon after, his father dies, which Salieri takes as a sign that God has accepted his vow. He prays to God that if He makes Salieri a famous composer, he will, in return, promise his faithfulness. Salieri recounts how, even in his youth in the 1760s, he desired to be a composer, much to his father's chagrin. The young priest Father Vogler approaches Salieri for elaboration on Salieri's confession. In the winter of 1823, Antonio Salieri is committed to a psychiatric hospital after surviving a suicide attempt, during which his servants overhear him confess to murdering Wolfgang Amadeus Mozart.

The story is set in Vienna, Austria, during the latter half of the 18th century, and is a fictionalized story of Wolfgang Amadeus Mozart from the time he left Salzburg, described by its writer as "fantasia on the theme of Mozart and Salieri". Amadeus is a 1984 American period biographical drama film directed by Miloš Forman and adapted by Peter Shaffer from his 1979 stage play Amadeus.
