This dissertation built and proposed an emergent Filipino komiks-to-film adaptation theory in the 1950s. It employed the grounded theory approach to unveil data that led to a contextualized, localized or indigenized study of adaptation. An inventory of extant texts led to the selection of four (4) films representing Filipinized genres such as the korido film, fantasy-adventure, comedy and historical film. The semiotic analysis drew from the approaches of Christian Metz, Raymond Bellour and Rick Altman. Contemporary adaptation criticism was also employed to explain constructs specific to Filipino culture. A social film history based on unstructured interviews with ten (10) key informants provided the context to the texts analyzed. This was supplemented by periodicals published in the fifties. The meta-issues of the theory addressed the state of the archives and current discourse. The concepts and assumptions about komiks-to-film adaptation supplemented the framework of the proposed theory that shall be called a vernacular and hybrid theory of Filipino film adaptation. Key words: source text, semiotics of adaptation, Filipino genres, adaptation criticism, Filipino film adaptation theory, vernacular, hybridity