It is a shocking picture of the last few months in a military prison for Polish officers before the Katyn massacre. Wasilij Zarubin, a Soviet secret service officer, after a failed mission in Germany is about to be executed but, in the face of a sudden outbreak of WWII, Stalin gives him a new task: his new mission is to enlist Polish officers from Kozielsk, Starobielsk, and Ostaszk—w camps to the Soviet Army.