CLEAN : FILE: Coen brothers to jointly head Cannes Film Festival jury

The transcript discusses the influence of a significant figure in music, suggesting that if you've ever heard three notes of music, this person is likely responsible. It then shifts to the challenges of casting in movies, emphasizing the importance of casting when a role is written for a very specific character.

What does the phrase 'three notes of music' imply about the character's influence?

In what ways is the character described as being significant in the movie?