Small-town boys Vähy and Hapa are best friends who swear an eternal blood oath. As they grow up, however, their paths drift apart and they both find themselves searching for their place in the world.
Sergeant Friman is developing an automatic submarine detector that piques the interest of both, Swedish and Russian spies.
The Minister of Defence asks sergeant Körmy to take part in operation, where the United States and Russia are to hand over their nuclear weapons launch equipment and codes to neutral Finland.
