Based on numerous interviews, technical reports and documentation, Bruno Latour traces the collapse of a large public transportation system project - the Personal Rapid Transit system named Aramis - in Paris. Latour's analysis of Aramis' history merges science and technology studies with the narrative form of a detective novel. The various actors in this story of a highly complex human-object-system - engineers, circuit layouts, engines, prototypes, rail track systems etc. - are all given an equal voice in a way that is of exemplary value for understanding the Actor-network theory. With the first German translation of this now classical study, the book series Historische Wissensforschung ( Studies in the History of Knowledge) launches its series "Under the Radar", which presents and contextualizes forgotten or hard-to-reach texts from the history of science.