When $300,000,000 in diamonds are stolen from a fiery plane wreck the British Government become concerned that it might be part of a plot to undermine the value of sterling. They hire professional photographer, amateur lady-killer, and undercover agent Steve Norton to investigate.
| Actor | Role |
|---|---|
 Richard HarrisonSteve Norton | Steve Norton |
 Alida ChelliUlla Helger | Ulla Helger |
 Luis DávilaGustav | Gustav |
 Diana LorysHuguette | Huguette |
| FFranco De RosaCapitano Darvi | Capitano Darvi |
 Rosalba NeriMargot | Margot |
| AAudrey McDonaldMrs. Van der Hoven | Mrs. Van der Hoven |
| RRoberto SpiombiDupuis | Dupuis |
 Alberto PlebaniVan der Hoven | Van der Hoven |
 José MarcoLarry Brooks | Larry Brooks |
| EEnrico CanestriniEdward Dwight | Edward Dwight |
 Ángel MenéndezYacht Captain | Yacht Captain |
 Goffredo UngerKurt | Kurt |
 Ferruccio ViottiLester Barrow | Lester Barrow |
 Attilio DottesioIl maggiore Hernandez | Il maggiore Hernandez |
 Giovanni Brusadori(uncredited) | (uncredited) |