Graeme Eadie was driving his two young sons home from their grandparents’ house. In the car in front, Kevin Duncan was driving dangerously, overtaking and slowing down with his headlights on full. So when they reached an intersection, Eadie jumped out of his car and grabbed his hockey stick and proceeded to beat Duncan to death. What causes this kind of radical, crazy road rage? Is it an individual’s mania, or is there a social cause?