The present article discusses the role of laughter in the much cited ‘laughter epidemic’ that occurred in Tanganyika in 1962. Despite its extraordinary nature, the veracity of the event is confirmed, crucially on the basis of similar reports. But most current representations are flawed by their exaggeration and misinterpretation of the role of laughter in the event, relating it to a humorous stimulus, a virus or environmental contaminant, or identifying it as contagious laughter. It is argued that the event is a motor-variant case of mass psychogenic illness of which laughter is one common symptom. Therefore it cannot serve as support for other arguments in humor research.