Grand challenges are complex problems that increasingly demand fields to interact with each other. The limited research on field-to-field interactions predominantly focuses on formal and durable structures to interact and sustain engagement of different fields. However, the maintenance of such structures risks diverting resources and focus from the underlying grand challenge itself. We draw on the notion of interstitial spaces as offering a compelling alternative for field-to-field interactions, providing informal and transient settings where actors from diverse fields can engage each other and generate novel practices that can survive beyond the lifespan of the structure itself. Building on a four-year inductive case study of ‘The Harvest’, an interstitial space focused on addressing the sustainability transition of the Dutch agriculture and food system, we detail the role that catalysts and interaction rituals play at various stages of its life. Our findings unpack the actors’ journey through two specific interaction rituals that conditioned their ability to more easily get back ‘in sync’ with different perspectives of other fields. We refer to this new practice as ‘resynchronizing’, enabling actors to sustain engagement around a set of perspectives rather than the static structure itself. We contribute to the literature and recent debates on field-to-field interaction and grand challenges, emphasizing the important role of interstitial spaces, and in particular the ability to resynchronize, when a shared take on the challenge remains an elusive quest.