Recent research suggests that serious gaming is a promising strategy for interprofessional education (IPE). This report describes the design and pilot testing of a large-scale, mobile, technology-enhanced serious game embedded in the IPE curriculum in Geneva, Switzerland. Organized into teams of eight, the students were tasked with finding a young patient who had just escaped from the intensive care unit. Through a series of 10 stations, they explored hospital- and community-based locations of the healthcare system and were engaged in various learning and game activities; they were rewarded with cues to unveil the mystery. A total of 582 undergraduate students from seven disciplines (medicine, midwifery, nursing, nutrition-dietetics, pharmacy, physiotherapy, and technology in medical radiology) took part. Survey results (response rate: 62.8%) suggest that an overall majority of students valued the game, particularly the collaborative experience of actively learning from others in autonomous teams. Qualitative feedback allowed us to identify future areas for improvement: simplifying the adventure storyline and optimizing student flow. Educational institutions across the world facing challenges when creating IPE activities will find in this report ideas and lessons learnt to use mobile technology and serious gaming for large cohorts of students.