Friedrich Glauser's Motto regiert (1936) tells a story with parabolic qualities: Sergeant Studer must investigate a murder that has taken place in a Swiss psychiatric clinic. The social and political issues that are roiling Europe in the years leading up to World War Two find condensed expression in this microcosm. The essay focuses on the literary devices the text employs to create atmosphere and asks how atmosphere functions both to support the construction of a classic murder mystery, while also subverting some of its generic conventions. The figure of the detective is of central importance, as he is portrayed as uncommonly sensitive to the atmosphere of his surroundings. At the same time, however, the clinic's atmosphere ultimately proves to some extent unreadable. Hence, Glauser's text can be viewed as a precursor of the what in post‐war literature will come to be known as anti‐detective fiction.