An auteur not only directs but also has creative authority over the film's vision. Quentin Tarantino is known as an auteur for his unique vision in films like Pulp Fiction.
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Distinct Style
Auteur implies a director's signature style that you can recognize across their movies. Wes Anderson's symmetrical frames mark him as a true auteur.
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Total Involvement
An auteur is deeply involved in writing, producing, and sometimes acting in their movies. Charlie Chaplin was an auteur, often taking multiple roles in making his films.