At least five directors were involved in the production, from Korda’s hapless original choice, Ludwig Berger, whom he came to dislike for his intimate approach to material that Korda had envisioned as grand and sweeping; to Michael Powell (brought in mainly to work with Veidt, whom he had directed in “The Spy in Black” and “Contraband,” Veidt’s first two British films); to the American action director Tim Whelan; and, when the production moved to the United States, to the influential Art Moderne production designer William Cameron Menzies and Korda’s more directorially accomplished brother, Zoltan Korda.
Source: wiktionary