In the present study, the three principal theories of Russian theorist Mikhail Bakhtin--the carnavalesque, grotesque, and dialogical--are applied to the musical-theatre genre of the Spanish zarzuela. The focus of the study centers on the works of composer Pablo Sorozábal and the various librettists who collaborated with him, among them the renowned literary author Pío Baroja. Within this study, zarzuela is first analyzed on its own in terms of the academic debate surrounding the genre and its importance in terms of both literary and musical criticism. After establishing the particular capacity of the zarzuela to make important cultural contributions, the central theoretical framework of the thesis is established via Bakhtinian theory, and several links are drawn between this theory and the genre of the zarzuela, which is shown to be a body of work often capable of conveying subversive messages, both cultural and sociopolitical. With this critical lens, then, the specific sociopolitical context of Spain between 1931-1942 is analyzed and described in order to illustrate the various extratextual and intertextual elements at play in Sorozábal's zarzuelas. The three works ultimately studied are Katiuska (1931), Adiós a la bohemia (1933), and Black, el payaso (1942). By way of highlighting the Bakhtinian characteristics at play in these three zarzuelas, the composer's intention to challenge and criticize Spain's sociopolitical reality, including Francoist dictatorship, is revealed, illustrating the capacity of the zarzuela to challenge and transgress existing norms--an aspect that many critics have failed to recognize in the genre up to the present day.