Hans von Oettingen

Inge Karsten receives an unexpected visit from her former student friend Margit from the West. She is even more surprised to hear that she is married to her stepbrother Herbert, who was long thought to be missing and whom she had almost forgotten. He last lived in Canada. This presents Inge's husband Horst, who has an important job as a military pilot, with a conflict of conscience. The situation is even more serious than it seems at first glance. In truth, Margit is an agent and the whole story is a staged game by the West German secret service...

In a casino in a West German health resort, one often sees Sybille - an attractive young student actress. With her winnings from the roulette table, she attempts to finance her studies. Despite a rather lucky streak, her winnings are a little on the lean side. She doesn't, however, gamble with her own money but with that of Dr. Busch, a lawyer, who likes to stay in the background with the argument that gambling houses are not the proper turf for a serious lawyer. From him, Sybille receives only a small share of her winnings later, and only through the intervention of Gerhard Fischer, a journalist, does Sybille come to realize her role in Dr. Busch's fraudulent scheme.