It is 1941, the first days the Continuation War between Finland and the Soviet Union. The place is Soviet Karelia, where Finnish troops have occupied Repola, a village burned by the Russians.

The mobile bicycle unit of young lieutenant EERO PERKOLA is ordered to the front lines at Repola. Three nurses arrive at the village by chance with a supply column. One of them is Perkola's fiancée, KAARINA VAINIKAINEN.

The meeting of the two young lovers in Repola is a surprise for both of them. Danger and a fear of the past cast a shadow over the joy of their reunion. Perkola goes to his commanding officer to request that the nurses be returned to the rear of the lines. The officer grants the request, hinting at the same time at a special mission. Perkola accepts it.

Perkolas unit sets out on a solitary reconnaissance mission at the enemy's rear. Their mission is to circle the Russian villages behind the enemy lines and scout the positions of enemy troops.

Kaarina is sent back with a transport of wounded soldiers. Russian partisans, in a surprise attack on the convoy, destroy it.

While en route, Perkola via a courier receives new orders from the headquarters. The unit is to continue their reconnaissance mission to the far side of the lake and join the Finnish offensive there. Perkola is also informed of the attack by the partisans.

These grim tidings mark the beginning of Perkola's personal war. During the course of the journey, he is transformed from a young and guileless officer into a seeker of vengeance. He closes his eyes to brutality and even becomes guilty of it himself. The mission is completed, but the price is dear.

Two soldiers in the unit exercise a strong influence on Perkola: Sergeant SAARINEN and Corporal LUKKARI, who represent clashing value systems. Saarinen is a gentle, religious man who even shows mercy toward the enemy. Lukkari is a hardened veteran of the Winter War.