Amadeus

From Conservapedia

Amadeus is a movie loosely based on Mozart's life, using the plot device of a supposed rivalry with Antonio Salieri (the first 10% of the movie is all about Salieri, even his encounter with the "giggling, dirty minded creature crawling on the floor"). The movie is based on the play of the same name by Peter Shaffer.

Salieri is jealous when the monarch employing him as a court composer commissions Mozart to write an opera in German. He is astounded to read some original sheet music (brought secretly by Mozart's wife); there are no corrections in them, as if he had the finished music in his head and was simply transcribing it.