Zwartjes made many films without dialogue or sound. The music can however be very important. Zwartjes composes it himself, sometimes together with his brother Rudolf and Lodewijk de Boer. Audition is a fine example of a Zwartjes film with an important soundtrack. It is a visual improvisation of cinematography and acting. There is hardly a ‘story line’. A man and a woman watch another woman singing, predominantly in exciting black and white images.