This paper presents an experiment in project/problem-based learning (PBL) in an upper division mathematical physics course. The group project in the course involved modeling a zombie outbreak of the type seen in AMC's The Walking Dead. Students researched, devised, and solved their mathematical models for the spread of a zombie-like infection. Students independently learned and utilized numerical methods to solve highly coupled systems of differential equations. This work explores student perceptions and reactions to problem-based learning, and the feasibility of using PBL as the sole pedagogy in upper division physics courses.