Let’s say we are asked to compose music for a film. A story must be told. We know that adding the wrong music will harm the film, will harm the story. So what should we do?
Basic emotions
Music is a trigger for emotions. Music creates feelings. And most people have a basic musical understanding and will feel the emotions which are transferred by music. Basic emotions like happiness and sadness for example can be transferred easily by using nothing more than a melody. But also the other basic emotions like anger, disgust, fear and surprise can be expressed through music.
A secret layer
Music can show us how the actor feels even without the need for the actor to express it by acting or using words. It’s a secret layer for expressing emotions.
A good example is the score that was composed and played by Ry Cooder for the film Paris, Texas (IMDb link). We hear Ry on acoustic guitar with a bottleneck on his pinky expressing the feeling of “sadness or depression of the spirits”. The feeling of melancholy, a longing for the past. And most of what is being said in the film is expressed without words through the music.