The ace pilot Lydia Litovchenko loses her wing-man during an air attack. One of the newly arrived pilots, Leonidas, is trying to impress Lydia with his skill. Ilya Bes arrives at the regiment.
In the very first sortie, Boris and Leonid violate the order and instead of defensive actions they engage in battle. As a result, many attack aircraft are killed, and young pilots are sent to the guardhouse.
Bes reprimands Boris about the merciless shooting of an unarmed German in the air and learns that in the past the whole family of the pilot was put up against the wall. A troika is sent to one of the tasks: Leonid, Boris and Terentyev.
The weather is bad and all flights have been canceled. Aerodrome signalmen are catching the call signs of some plane lost in the fog. The plane turns out to be ours. The pilot is calling for help: he is running out of fuel.
Finding himself in the rear of the Germans, Bes meets his grandfather on the road, who hides him in a haystack and brings him to a village captured by the Germans. This is how the Bes is captured.
Bes is captured by Wehrmacht, run away from the village. The Germans are chasing, but Bes manages to escape. In a depressed state, Lydia leaves the hospital - she was forbidden to return to the regiment.
Terentyev insists that Bes is a saboteur. Lydia returns from her native village to the regiment. The special officer advises Terentyev to lag behind Bes. Leonid invites Lydia to dance, but she refuses him,and she herself comes up to Boris.
The Consolidated Aviation Regiment was relocated to the immediate vicinity of the mysterious square. An awkwardness arises between Lydia and Boris - they do not know how to take the next step.
Evgenia tells the general that the enemy is concentrating unprecedented forces in the square. The regiment commander orders several fighter pilots to reinforce the convoy of the general's transport plane and provide him with protection.
Gunsmith Svetlana is four months pregnant by Terentyev. Evgenia at U-2 delivers ammunition to the partisans and finds out where the German warehouses are.
The pilots fly over the mysterious square again. The wing-man of one pair loses height, is forced to descend and discovers traces of tanks that reach the river. Boris proposes a risky plan.
All pilots from the nearest airfields are being pulled to the base. There is a fierce battle. Below, shells exploded, German tanks crawling. Egor drags a machine-gun belt to Leonid. Lydia's plane is knocked out,
