In the face of two world wars, Professor Prätorius, a philanthropist and a surgeon, wants to exterminate the one danger to mankind, the microbe of stupidity, as he states in a spontaneous lecture to his male and female students. When he tries to help a pregnant girl he gets involved more and more in her life and is forced to marry her.
| Actor | Role |
|---|---|
 Curt GoetzDr. med. Hiob Prätorius | Dr. med. Hiob Prätorius |
 Valerie von MartensMaria Violetta | Maria Violetta |
 Albert FlorathPastor Höllriegel | Pastor Höllriegel |
 Erich PontoProfessor Speiter | Professor Speiter |
 Bruno HübnerNot listed | Not listed |
| RRudolf ReiffNot listed | Not listed |
| PPaul MederowNot listed | Not listed |
 Hedwig WangelNot listed | Not listed |
 Gertrud WolleNot listed | Not listed |
| EEugen DumontNot listed | Not listed |