Operation "Resident", which lasted 15 years, is coming to an end. But the indestructible agent of "Nadezhda" has one important mission left. Agent Carl Brockmann, who intends to steal the work of Academician Nikolai Nesterov in the defense sector, has been abandoned in the USSR. KGB leadership asks Mikhail Tulyev to return to the Soviet Union to find the spy. Meanwhile, Brockmann recruits former fascist collaborator Mikhail Kutepov for involvement in a dangerous operation.

After Tulyev's arrest, Soviet counterintelligence continues the radio game with the enemy, sending encryptions signed "Nadezhda" to the Western intelligence center. KGB officer Sinitsyn, friendly towards Tulyev, tries to persuade him to take his side — he arranges a meeting to a scout with Mariya and her son, whom he has never seen before. In addition, Mikhail learns that his father didn't die of his own death, but was most likely killed. Meanwhile, a young Soviet scientist Borkov, who spoke at an international conference about his innovative work, finds himself in the spotlight of the Western security services.

In this thrilling mystery movie, a secret agent makes a blunder that sets off a chain of unforeseen events. As he tries to rectify his mistake, he finds himself entangled in a web of deceit and danger.

After returning from the USSR, Tulyev was subjected to rigorous verification of his former "owners". He continues his work in Western intelligence, but already as a Soviet intelligence officer through the First Main Directorate of the KGB of the USSR. In a new capacity, he establishes the whereabouts of Hitler’s criminal Hoffmann, who was once sentenced to death, and helps the authorities arrest him. However, as a result of the conflict within NATO intelligence, Charlie Brighton, Hoffman's assistant, begins to hunt for him. At the same time, Tulyev manages to establish the identity of the murderer of his father, Karl Brockmann, with whom they crossed in the service of mercenaries somewhere in hot countries. He wants revenge, but, by an evil irony of fate, he must help prepare Brockmann for being cast as a spy in the Soviet Union.