The story about Gustaf Dalén, the farm boy who became one of Sweden's greatest inventors.
| Actor | Role |
|---|---|
 Olof BergströmGustaf Dalén | Gustaf Dalén |
 Eva StibergElma Persson / Elma Dalén | Elma Persson / Elma Dalén |
 Gunnar BjörnstrandHenrik Kugelström | Henrik Kugelström |
 Kolbjörn KnudsenAnders Johansson | Anders Johansson |
 Erik StrandmarkMellander | Mellander |
 Gunnar SjöbergGustaf De Laval | Gustaf De Laval |
 Åke ClaessonProfessor Wijkander | Professor Wijkander |
 Märta ArbinLovisa Johansson | Lovisa Johansson |
 Carl StrömHöjer | Höjer |
 Hans StrååtAlbin Dalén | Albin Dalén |
 Gunnar OlssonAnders Persson | Anders Persson |
 Olle HildingBergquist | Bergquist |
 Ernst EklundBank Manager | Bank Manager |
 Björn BerglundPettersson | Pettersson |
 Gösta PrüzeliusEngineer Gyllsdorf | Engineer Gyllsdorf |
| JJan von ZweigbergkNyquist | Nyquist |
 Ingvar KjellsonEngineer Borg | Engineer Borg |
| RRolf HuhtaniemiYoung Gustaf Dalén | Young Gustaf Dalén |