Front

Vlad Volny, is recruited by the Soviet secret services to obtain information about the developments being carried out in the German Auerge Design Office. He meets a talented physicist, a former prisoner of a German concentration camp of Polish origin, Katerina Shtur. She is a member of the group of scientists who, under top secrecy, are developing a nuclear weapon.

Trokhin, the commander of the intelligence group, receives a new order - to urgently bring the head of the "Auerge" laboratory (Guts) to Moscow. Having received the task, Vlad persuades Katerina to take Guts out of the protected building, promising to snatch her from the clutches of the Nazis and smuggle her to a secure place.

Vlad and Katerina managed to break through the German cordons, they get to the Polish guerrillas. The plane on which the guerrillas send the fugitives does not reach the front line, and Vlad and Katerina have to get to the Russians in the woods by themselves. They are chased by the Germans with dogs.

The German intelligence follows the trail of the disappeared scientists. Finding the corpse of Guts and receiving the order of Admiral Canaris to cut off the transfer of Katerina to the Russians, the head of intelligence Meyers gives the order to find and return Shtur - dead or alive.

The Germans are developing a new operation. If at the beginning they tried by all means to block Katerina's way to the Russians, now she has pinned her hopes on Shtur, who must convince the Russians that the Germans uranium program is not a myth. Her mission must end there. Anna, who is a German agent is given an order to remove Katerina.

Vlad manages to get to the Russians. In the Soviet bases he is looking for Katerina. Hlopko offers Anna a deal. The German command shall give the opportunity to leave the USSR to him and his family; in exchange he is willing to grant the access to classified information of his Department.

Frightened by stories about the fate of Soviet scientists Katerina persuades Vlad to flee.

Litvin has the last chance to execute the order to destroy Shtur. He knows that Katerina is planned to be taken out of the city and be sent to a new place of work and plans to ambush her. He has no idea that the transfer of Katerina is the operation that is developed by the Soviet intelligence service to destroy the network of residents, including Litvin.