The Thief of Bagdad (1940)
Filmmaking is a collective enterprise, and it has been so almost since its inception. As every new storytelling tool demands additional crew members to oversee it, and since the cinematic grammar never stops evolving, movie production has unfolded into an endeavor that nowadays comprises thousands of people. Even though, as a consequence, the responsibilities delegated to each role in such massive crews can become considerably fuzzy, it is still widely accepted that a movie as a whole is (and has always been) the result of the creative vision of its director above everyone else: swap the producer, replace the editor or have the script altered during filming, and the ensuing movie will arguably still be the same overall; change its director, however, and you risk having an artistically fragmented mess of an outcome. That is, unless the true auteur behind that film is not its director, but in fact its producer , something that was quite common during the old Hollywood Studio Era