The aim of this contribution is to help develop a new model of the use of storytelling in planning. To this end, it draws on media studies research as well as literary studies that examine so-called transmedia storytelling devices. The authors use this method to examine the communication strategy around the 2030 Cantonal Master Plan of the Republic and Canton of Geneva (Switzerland). This communication strategy, which attempts to construct the reception of development projects, mobilizes practical regimes that can strengthen the engagement of different audiences with the process of giving narrative form to future urban developments. Communication and public participation in an urban project tend to hybridize, thereby complexifying debates on the use of storytelling in planning, which often contrast its educational use (explain projects to the general public) with its manipulative use (make projects desirable so they may be accepted). By conducting an analysis through the prism of transmedia storytelling, we can simultaneously consider these two aspects of communication in planning.