INTRODUCTION: Many healthcare education commentators suggest that moulage can be used in simulation to enhance scenario realism. However, few studies investigate to what extent using moulage in simulation impacts learners. We undertook a mixed-methods pilot study investigating how moulage influences student immersion and performance in simulation. METHODS: Fifty undergraduate paramedicine students were randomized into two groups completing a trauma-based scenario with or without patient moulage. Task immersion was determined via a self-report questionnaire (National Aeronautics and Space Administration Task Load Index), eye-tracking, and postsimulation interviews. Performance was measured via independent observation of video by two paramedic clinical educators and time-to-action-when students first applied pressure to the primary wound. RESULTS: Eye-tracking suggested that students attended to the thigh wound more often with the inclusion of moulage than without. National Aeronautics and Space Administration Task Load Index data suggested that the inclusion of moulage heightened students' feeling of being rushed throughout the scenario. This elicited an expedited performance of tasks with moulage present compared with not. Students experienced greater immersion with the inclusion of moulage. However, including moulage enhanced scenario difficulty to the extent that overall clinical performance was negatively affected. However, no differences were found when more heavily weighting items felt to contribute most to the survivability of the patient. CONCLUSIONS: Including moulage engendered immersion and a greater sense of urgency and did not sacrifice performance of key life-saving interventions. As a result of undertaking this pilot project, we suggest that a large-scale randomized controlled trial is feasible and should be undertaken before implementing change to curricula.