I think that the use of films is significant because it helps to provide the foundation for both men moving closer to one another.  It gets to the point where Valentin asks for Molina to recite his films.  While Valentin initially rejects the notion of Molina's film narration, he comes to understand that it is a part of him.  At the same time, Valentin no longer rejects the content of Molina's films as he relays them over time.  He understands that they are a part of Molina and while he might politically object to them, he acquiesces to them because of their importance to Molina.  It is here where we start to see a potential for consensus in a world rife with antagonism.  Valentin still holds on to his political idealism, but understands that there are some realms of the private where it can be suspended for there is no struggle to be reached.  At the same time, Molina's understanding of how Valentin becomes closer to him, shown by his acceptance of the film narration, helps to move Molina closer to embracing the political ends that Valentin asks of him as their time comes to a close.  The narration of films becomes significant because it moves both men closer to the polarity that was initially rejected at the start of their relationship.  In doing so, Puig is able to construct a setting where the use of films provide a realm where change in human beings is evident, demonstrating the potential for emotional and spiritual transformation through art.