Casablanca

Casablanca contains many leitmotifs. Probably the most obvious leitmotif in the film was Rick and Isla’s love theme of “As Time Goes By,” played when they are together in the movie. This theme had many variations throughout the film, whether it was being played by Sam on the piano as source music, or by an orchestra as part of the underscore. This theme is not played during all times that they are together. I noticed that when they met in the marketplace the day after Ilsa had tried to talk to him after hours in the club while he was drunk, their theme was not played. I think that it was left out of this scene to show the tension and distance that existed between them.
The German officers /Reich have their own theme as well. When they are shown performing their military duties (ie. making an arrest, pursuing someone, when Major Strasser is driving to the airport to stop Victor and Isla’s plane from leaving, etc.) the music creates a feeling of tension through the loud trumpets blaring and low drums.
The composer utilized Moroccan ethnic instruments to create musical color during scenes in the marketplace and the Blue Parrot. However in Rick’s club, the piano music has a bouncy rhythm to it, giving it an American feel (after all, it is an American themed club). During scenes in the club the music is almost always diagetic. Sam, the lady playing the guitar, or the band is usually shown playing the music, or if they’re not shown, it is inferred that they are playing. Often the music that is played in the club becomes the underscore as the scene changes.