The book is devoted to the activities of military counterintelligence officers of the NKVD of the USSR in the first ten months of World War II: from the border battle to the completion of the Red Army counteroffensive near Moscow in April 1942. It was at this time that the fate of our Motherland was decided, the events of these days had a significant impact on the course and outcome of the entire war. Therefore, in an emergency, the work of special departments was restructured, the forms and methods of confronting the enemy were tested in practice, and experience was gained in the fight against the special services of Germany and its allies. The publication will tell about unknown facts of difficult everyday and specific work of military counterintelligence officers in units and subunits of the army and navy, at the front and in the front line.