What happens to literary voices when they are transposed into another medium? This is the central question of this study, which takes as its primary focus Céline’s 1932 Voyage au bout de la nuit, Queneau’s 1959 Zazie dans le métroandtheir adaptations into a variety of media, namely illustration, comic book, film, recorded reading and stage performance.Through the lens of the model of ventriloquism and with a theoretical framework that includes post-structuralist theories of voice and Bakhtinian dialogism, the analysis first reveals differing modes of relationships between voices (narrator’s and characters’) in Voyage and Zazie, in terms of vocal control and vocal power. The analysis then moves ontothe further layers of complexity added to the voices of Voyage and Zazie in the adaptations. The literary voices, and the different ventriloquial relationships between narrators and characters,are re-configured through the relationship between text and image (in illustration and comic book), between the soundtrack and the imagetrack (in film),and through the use of the dynamics of voice (in acting). My analysis of ‘voice’, firstly within the texts and secondly in their adaptations, aims to reveal how ‘voice’remains in a permanent process of construction. The study, then, explores how textual vocality is createdthrough ventriloquism and relationships of control and power between voices, and how it is actualised and transposed in adaptation.I suggest that the ways in which the textual voices of Voyageand Zazieare, in turn, challenged, empowered, trapped, uniformised or dislocated in the adaptations show the cyclicality of loss and gain with regard to voice. I seek to demonstrate that voice isconstructed in a dynamic of appropriation and expropriation, through the dialogue between one’s voice and the other’s voice, between the unfinished textual voices and the readers’ and adapters’ own voices.