The film "Die Unbesiegbaren" covers an episode in German history, in which the Bismarck government tried to mitigate the rise of the social-democrat movement.
Professor Mauthner, after many years of exile (having emigrated in 1933 to the USA), returns to Germany in 1948. He can in fact return to his teaching post, but the rejection and petty intrigues of his reactionary colleagues and students make his work almost unbearable.
