A cunning jewel thief has been giving Scotland Yard Inspector Grey a hard time for a long time. Nobody suspects that the man keeping the police on their toes is the likeable Roger Edgeston, the son of the Duke of the same name. When the shrewd crook meets the enchanting Jennifer Lindsey on a cozy summer night, fate takes its course, as the charming young lady also engages in criminal activities in her spare time and acts as a blackmailer. In the course of the evening, the duke's son is forced to realize that love is not only blind, but also careless when it comes to his illegal activities.
| Actor | Role |
|---|---|
 Carl WeryDechant Lindsey | Dechant Lindsey |
 Liselotte PulverJennifer Lindsey | Jennifer Lindsey |
 Richard HäusslerRobert Grey | Robert Grey |
 Joachim FuchsbergerRoger Duke of Edgestone | Roger Duke of Edgestone |
 Albrecht SchoenhalsDuke of Edgestone | Duke of Edgestone |
 Trude HesterbergDuchess of Edgestone | Duchess of Edgestone |
 Else QueckeRosie | Rosie |
| SSonia SorelBaronesse Childrake | Baronesse Childrake |
| WWalter HoltenDirector of Scotland Yard | Director of Scotland Yard |
| KKarl SchaidlerButler | Butler |
| DDietrich ThomsConstable | Constable |
| KKonstantin DelcroixFirst Jeweler | First Jeweler |
| JJochen HauerSecond Jeweler | Second Jeweler |
| AAlbert SpengerThird Jeweler | Third Jeweler |
| IInge BenzFirst Saleswoman | First Saleswoman |
| AAnneliese von EschstruthSecond Saleswoman | Second Saleswoman |