Magnum Opus n.
1. A great work, especially a literary or artistic masterpiece.
2. The greatest single work of an artist, writer, or composer.
This list is a collection of Magna Opera from some of the most famous Film directors of all time.
Whether I have seen the film or not, I will list it, if I believe that film to be highly regarded as the Magnum Opus.
Listed alphabetically by last name.
The choices are the films I believe to be their masterpiece(s), based on my own opinions (if I have seen the film) and/or their overall respect by audiences and critics.
I have chosen to use Director items instead of Film items because some directors have two or more films that can be considered their masterpiece.
If one director has 3 films and another only has 1, it doesn't mean that I believe the director with 3 is a better director. It just means they has more films that can be considered a masterpiece over the other, whereas some have a film that can be easily considered their Magnum Opus because the film in question is generally more famous and/or clearly regarded as their best work.