by composer Ralph Benatzky and contained music by Irving Berlin, Jerome Kern and many others. After the series of revues, Charell began adapting classic operettas such as The Mikado, , Madame Pompadour and Die lustige Witwe and turned them into modern jazzy revue operettas, claiming that he needed a plot line for his show, that had been missing in the pure revues before. A few years later, he decided to create his very own operettas with composer Ralph Benatzky. Together they wrote the trilogy of historical revue-operettas, which made Charell famous to this day: Casanova (1928), (1929) and The White Horse Inn (Im weißen Rößl, 1930). Especially The White Horse Inn was one of the most successful creations of Charell's career. In the following years he himself staged the show in London (1931), Paris (1932) and New York (1936), where each production was newly conceived, the script translated differently, and new music and instrumentation were added in some parts. Many actors and singers, such as Marlene Dietrich, Joseph Schmidt, Max Hansen and Camilla Spira, who all became famous later, first appeared in major roles in Charell productions. Charell also discovered the boy group Comedian Harmonists and presented them for the first time in Casanova at the Große Schauspielhaus. The reaction of the international press was positive, the New York Times noting that “Erik Charell seems to have done it again. 'Casanova', his latest operetta production at the Grosses Schauspielhaus, is filling this huge circus to its stylized rafters”. After this string of stage successes, Charell moved on to the new and innovative genre of sound film operetta. In 1931, Universum Film AG (Ufa) producer Erich Pommer invited Charell to direct Der Kongreß tanzt, (sets by Ernst Stern, music by Werner Richard Heymann), one of the most successful films of the early era of sound film, with one review in the New York Times saying that “[it] is a stupendous pictorial film. […] it is […] an exceptional film entertainment. The director, Erik Charell, is the Ziegfeld of the German musical comedy stage” and another noting that “It is a charming spectacle of Vienna in 1814, filled with tuneful melodies that one likes to remember and blessed with pleasing light comedy”. The international success of Der Kongreß tanzt led to an engagement in Hollywood, where Charell directed the movie Caravan, again with sets by Ernst Stern and music by Werner Richard