The stories we tell about the future shape our collective imagination of technology, ecology, and multispecies coexistence. Here we present a design research pipeline that operationalizes thematic insights from speculative fiction to create interactive digital narratives (IDNs) for exploring human–plant–computer futures. Using a corpus of ten science-fiction works, we conducted a thematic analysis to identify recurring patterns in plant representation, interaction types, functional roles, and ethical themes. These insights informed a structured ideation process, storyworld design, and low-fidelity prototyping of interactive concepts, culminating in an augmented tabletop role-playing game that integrates VR immersion and AR-based plant interaction. This reproducible pipeline establishes a novel pathway for designing IDN systems directly from speculative narratives, enabling the creation of interactive artefacts that embed multispecies ethics and ecological storytelling into their core design.