A lock factory worker Pertti would like to marry his girlfriend Verna, but fears they don't have enough money. His brother Martti is a member of a youth gang that is planning a robbery with three other young men. When the boys have to flee at the time of the robbery, Pertti who secretly shadowed them sees an opportunity to solve his money problem.
In the 1880s, an unruly group of Cossacks stays in Sankola's house in Hämälä. Soon the group's leader Kuisma sets his sights on the house's adopted daughter Helina . Isma, the owner of the farm, has also fallen in love with Helina.