Braudy ( The World in a Frame: What We See in Films, 25th Anniversary Edition ) uses the character of Rotwang from Fritz Lang’s Metropolis to make the point that the best films are about the potentials of film. Rotwang is a mediating figure in Lang’s film, living above ground like the managers, but having a stairway from his cellar to the workers’ quarters below. He is a scientist, but he dresses like a magician.
For Braudy, “Rotwang is a paradigm of the film director, who attempts to mix scientific knowledge with the primeval magic of artistic creativity, who sympathizes with the masses because they are the basis of his art at the same time that he is tempted to sacrifice them to the managers who give him his livelihood.”
The same self-referentiality is evident in the popularity of monster films, which Braudy thinks arise from something deeper than “public demands for horrific titillation”: “such works perform a twin function, for they both define something of the audience’s fears of the twentieth century as well as something essential about the nature of film as a medium and the way in which it caters to, expresses and, by art, allays those fears.” Films can both “embody some theme that is deeply rooted in the emotions of its audience” while at the same time delivering “a disquisition on its own artistic nature and why such themes are so suited to it.”