The Invisible Front (1932)
The Invisible Front, or A submarine spying film or Ein U-Boot-Spionage-Film in German, is a German cloak-and-dagger-movie from 1932, directed by Richard Eichberg and starring Trude von Molo, Karl Ludwig Diehl, Veit Harlan and Paul Hörbiger. The story was written by Robert A. Stemmle, Curt Siodmak and Max W. Kimmich, who also presented the idea to this film to his colleagues.
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