Soviet Union attacked Finland in late November 1939. This film tells the story of a Finnish platoon of reservists from the municipality of Kauhava in the province of Pohjanmaa/Osttrobottnia who leave their homes and go to war. The film focuses on the farmer brothers Martti and Paavo Hakala.

The Soviet forces had four times as many soldiers as the Finns, 30 times as many aircraft and 218 times as many tanks. However, the Red Army had recently been subjected to a drastic purge in 1937 that crippled it, reducing its morale and efficiency shortly before the outbreak of hostilities. With up to 50% of army officers executed, including the vast majority of those of the highest rank, the Red Army in 1939 had many inexperienced senior officers. Due to a combination of these factors, and an extremely high commitment and morale in the Finnish forces, the Finns were able to resist the invasion of their country with great success and for far longer than the Soviets had expected.