1942. Against the backdrop of a decline in military morale, the difficult task becomes distinguishing the traitor from one's own. Once held captive by the enemy, Major Toporkov bears a stigma that makes it difficult to regain the trust of his own front. However, he possesses important information for the partisans and is ready to prove his loyalty to the country. Having received a convoy of weapons and a volunteer squad, he leads them to a concentration camp where a rebellion is being prepared. But among the brave soldiers, there is a traitor who informs the Germans of their every move.