TV Movie | | Biography, Drama, History
When Erich Kästner and Hans are sitting together they make up a story about how only parents of twins should be divorced, so each parent can get a child and they can switch places. This story later became Kästners novel "Das doppelte Lottchen" (Lottie and Lisa), released in 1949 and was the source for "The Parents Trap".
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Erich Kästner mentioned to Hans that he is writing a funny screenplay for Heinz Rühmann, which would be a direct reference to Ich vertraue Dir meine Frau an (1943), where Heinz Rühmann is playing the lead. The scene is set in 1936 but the movie was released in 1943. However he could have meant that the writing process is going on, before the movie is released. The movie had several screenplay versions.