The purpose of the research is to identify frequent archetypes in american science ficction movies. Starting from the definition of movie gender and the analysis of the archetype role in film narrative, Jung s archtype model will be used in order to establish the two most frequent myths in Hollywood´s sci-fi universe. The creature, brought up by some techonological discovery, turns its back on its creator as in Prometeu in chains, and the invader, a technologicly more equiped alien civilization that comes to conquer our planet and destroy our way of life. Two of german film-maker Roland Emmerich s movies will be used as corpi. Independence Day, as an example of the invader archetype and The Day After Tomorrow, to illustrate the criature mythological archtype.