In a made-up country somewhere in northern Europe: In the armaments factory F.N.G., an important drawing is copied and passed on to the enemy. Suspicion falls on the chief engineer Alexander Nica and his assistant Laurenz. Both are placed before the court; accused by the night watchman Bruns; and sentenced to death for industrial espionage. Before sentencing, however, Nica succeeds in getting away. Now he’s trying to find proof to convince the court of his and Laurenz’ innocence.