Fabian von Schlabrendorff trained as a lawyer, later joining the German Army. As a lieutenant in the reserves, he was promoted to adjutant to Colonel Henning von Tresckow, a major leader in the resistance against Adolf Hitler. He joined the resistance and acted as a secret liaison between Tresckow in Russia and Ludwig Beck, Carl Goerdeler, Hans Oster, and Friedrich Olbricht in Berlin, taking part in various coup d'état plans and plots. Wikipedia
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