The plot of the series "His Excellency's Adjutant" is based on real historical events from the life of our country. In the midst of the Civil War, the Red intelligence agent Koltsov successfully infiltrates the rear of the White Denikin army, where he becomes the adjutant to the commander. His beliefs are put to serious tests, and at some point Koltsov has to choose between what is right and what is easy. Thanks to his efforts and the invaluable information he supplies, the war experiences a significant turning point.