This article describes the authors' work as formative evaluators of a mixed-reality science museum installation, Journey with Sea Creatures. Looking beyond the focal point of the screen to the spatial and temporal surroundings of the exhibit, the authors employed a technique they call retrospective narrative mapping in conjunction with sustained on-site observations, follow-up interviews with museum visitors, and the development of personas to better understand the user experience in multimodal informal learning environments. © 2009 Taylor & Francis.