This is without a doubt the weirdest movie you will ever see, leaving you uneasy from beginning to end. This is re-enforced by the soundtrack that Stanley Kubrick used. He only had one piece of music actually recorded for the film, and that was the theme music, written by Wendy Carlos, who he would work with nine years later for The Shining.
A Clockwork Orange is unique because it uses atonal, almost electronic sounding music, such as the theme linked above, but also famous classical pieces.
The main character, Alex (played by Malcolm McDowell), loves his Beethoven, and during several key parts of the movie, you can hear the ninth symphony/second movement. The music is even used in the most crucial scene of the movie, during a scientific experiment on Alex. Will not say any more to avoid spoilers.
We also get to hear two different movements of Edward Elgar’s Pomp and Circumstance. Guarantee you will never sit through another graduation ceremony in the same way again!
Last but not least, who could forget Singin’ in the Rain, sung by Gene Kelly, that is played during one of the most disturbing scenes in the film.
Stanley Kubrick always made sure to use great music in his movies, and this one would not be the same without the different moods captured in the various pieces, to make the audience feel uneasy. But because there was only one piece of original music composed, it gets the nod at number ten on my list.