With this edition, previously unknown French-language letters by Juliane Franziska von Buchwald, first lady-in-waiting to Luise Dorothea von Sachsen-Gotha-Altenburg, are presented for the first time in an annotated German translation. In the summer of 1738, under the guise of concern for her mother, Frau von Neuenstein, governess at the court of Württemberg, she began to correspond with Christoph Dietrich von Keller. As a lawyer and envoy of Württemberg at the court in Vienna, he was about to embark on one of his numerous political missions, which not only interested Saxe-Gotha-Altenburg. The letters of Buchwald, who describes herself as an agent, accompany the time of the War of the Austrian Succession with ever more sophisticated encryption, embedded in a choreographed communication strategy. The correspondence with Keller, who was already praised by contemporaries as a brilliant letter writer, ended in 1750 shortly before he was appointed to the Gotha Privy Councilor and as a result of the almost complete blindness of Buchwald after an unsuccessful eye operation.