Shadows on the Isthmus (Varjoja Kannaksella) 80 years old

Lieutenant Ville Somero (Matti Lehtelä) 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 (Aarno Kivistö), an engineer leading the fortification site, and his bride Birgit Lahti (Anna-Liisa Sarvanto) get into trouble because of a band of spies and dancer Veronica Sorrento (Dolly von Alfthan).