Kalle Blomkvist and his friends intervene when a professor and his little son Rasmus are kidnapped.
| Actor | Role |
|---|---|
| LLars-Erik LundbergKalle Blomkvist | Kalle Blomkvist |
| PPeder DamAnders Bengtsson | Anders Bengtsson |
| IInger AxöEva-Lotta Lisander | Eva-Lotta Lisander |
| EEskil DaleniusRasmus Rasmusson | Rasmus Rasmusson |
| SSam StadenerSixten | Sixten |
| UUlf SöderbergBenka | Benka |
| GGöran RyrbäckJonte | Jonte |
 Sigge FürstPoliceman Björk | Policeman Björk |
 Elof AhrleNicke Karlsson | Nicke Karlsson |
 Ulf JohanssonPeters | Peters |
 Björn BerglundProf. Rasmusson | Prof. Rasmusson |
 Arne KällerudKalle's Father | Kalle's Father |
 Solveig HedengranKalle's Mother | Kalle's Mother |
 Britta BruniusMia Lisander | Mia Lisander |
 Börje MellvigStenberg | Stenberg |
 Birger ÅsanderBlom | Blom |
| HHarry PhilipsonEva-Lotta's Father (uncredited) | Eva-Lotta's Father (uncredited) |
| GGustaf Hiort af OrnäsBerggren (uncredited) | Berggren (uncredited) |
 Eric von GegerfeltChief Constable Öman (uncredited) | Chief Constable Öman (uncredited) |
| OOlle EkbladhState Police (uncredited) | State Police (uncredited) |