Film is set in the winter of 1942 during the Nazi occupation of Russia in WWII. Partisan guerrillas, headed by Ivan Lokotkov, are testing the POW Lazarev, who briefly collaborated with the Nazis for survival. Lazarev is not executed, but instead he is given a chance to prove his loyalty. He has to go back to the Nazi controlled railway station, where everyone knows him, and to hijack a train with food supplies. Lazarev proves himself a hero.