Two nine-year-old girls—rude Luise Palfy and respectful shy Lotte Körner—meet on a summer camp. Apart from their different hair-do, they look alike. They have never seen each other before, but soon find out that they are identical twins. It turns out that their parents divorced, each keeping one of the girls. They decide to trade places at the end of the summer. Lottie curls her hair, Lisa braids hers, and both go off to where they have never been before. The adventure begins.
| Actor | Role |
|---|---|
 Erich KästnerNarrator | Narrator |
 Antje WeisgerberLuiselotte Körner | Luiselotte Körner |
 Peter MosbacherLudwig Palfy, Opernkapellmeister | Ludwig Palfy, Opernkapellmeister |
| JJutta GüntherLotte Körner | Lotte Körner |
 Isa GüntherLuise Palfy | Luise Palfy |
 Senta WengrafIrene Gerlach | Irene Gerlach |
 Hans OldenHofrat Strobl | Hofrat Strobl |
 Auguste PünkösdyResi | Resi |
| MMaria KrahnFrau Muthesius | Frau Muthesius |
 Gustav WaldauNot listed | Not listed |
 Liesl KarlstadtFrau Resi Wagenthaler | Frau Resi Wagenthaler |
 Inge RosenbergFräulein Ulrike | Fräulein Ulrike |
| GGaby PhilippFräulein Gerda | Fräulein Gerda |
 Walter LadengastHerr Gabele | Herr Gabele |
 Gertrud WolleFräulein Linnekogel | Fräulein Linnekogel |
| HHertha von HagenNot listed | Not listed |
| LLiselelotte BerkerNot listed | Not listed |
| GGerda SommerschuhNot listed | Not listed |
 Rudolf RhombergPhotographer | Photographer |
| IIna GerheinNot listed | Not listed |
| KKatja SaboNot listed | Not listed |
| PPaul KuenNot listed | Not listed |
| FFriedrich BenderNot listed | Not listed |
 Senta BergerExtra (uncredited) | Extra (uncredited) |