Lieutenant Ville Somero investigates a sabotage at a fortress site on the Karelian Isthmus in the summer of 1939. His suspicions are directed at the guests of a nearby guesthouse. Aarno Teräs an engineer leading the fortification site, and his bride Birgit Lahti get into trouble because of a band of spies and dancer Veronica Sorrento.
Matti Lehtelä
Dolly von Alfthan
Ensio Jouko
Aarno Kivistö
Anna-Liisa Sarvanto
Verna Piponius
Sven Relander
Aune Häme
Runar Schauman
Eero Leväluoma
Vilho Siivola
Erkki Uotila
Joel Asikainen
Kerttu Salmi
Eino Haavisto
Oiva Turunen
Urho Virta
Pentti Saares
Armand Lohikoski