When the mathematics teacher discovers a love letter from his daughter, family father Felix Schneider is suspected of having a secret lover.
| Actor | Role |
|---|---|
 Heinz RühmannDr. Felix Schneider | Dr. Felix Schneider |
 Hans MoserProfessor Karl Stieglitz | Professor Karl Stieglitz |
 Theo LingenPaul Fellmeier | Paul Fellmeier |
 Nadja TillerOlga Fellmeier | Olga Fellmeier |
 Annie RosarLilli Schneiders Mutter | Lilli Schneiders Mutter |
 Gusti WolfHilde | Hilde |
 Chariklia BaxevanosHertha Nepalek | Hertha Nepalek |
| HHilde BerndtLilli Schneider | Lilli Schneider |
| BBrigitte RatzBrigitte Schneider | Brigitte Schneider |
 Lotte LangMarie (Dienstmädchen) | Marie (Dienstmädchen) |
| MMargarete SlezakRosi Stieglitz | Rosi Stieglitz |
 Egon von JordanDr. Haberer | Dr. Haberer |
| FFritz HellerHerr Kraus | Herr Kraus |