This contribution reflects on a shared teaching experience with Rocco De Nicola that unfolded from 2006 to 2009 at the IMT School for Advanced Studies in Lucca, Italy. During this period, we co-taught a course on formal methods based on process algebras, including Milner’s Calculus of Communicating Systems (CCS). While the course underwent yearly changes in nomenclature and content, it was there that we started using a logical puzzle known as the “50 prisoners puzzle” as a pedagogical tool for CCS modelling and analysis. By bridging theoretical abstractions with concrete problem solving scenarios, we empowered students to grasp the intricacies of process algebras while fostering critical thinking and problem-solving skills. Subsequently I revisited this very same example in subsequent MSc level courses, which I teach at the University of Pisa.