The main character is the chekist Fyodor Dyatlov. He is in love with his friend Hippolytus' sister, the educated, intelligent Irina. At the same time, he harshly pursues the younger brother of Hippolytus and Irina Valerik. He is also a security officer, but in his youth he was tempted by a bribe. Fyodor investigates the case himself and puts Valerik in the hands of higher security officers. His possible happiness with Irina and his friendship with Hippolytus are at stake. But Fyodor is a real fanatic of the communist idea. For the sake of principles, he will do anything.