Suspiria: Everything You Need To Know About The Three Mothers
5. Mother Tenebrarum
Appearing in the follow-up to Suspiria, Mater Tenenbrarum was the primary antagonist of Inferno.
This is also notable for being the first time that Argento outright committed to the idea of the Three Mothers. Suspiria is obviously a part of the trilogy but never mentions anything about the other Mothers. Whereas Inferno's plot hinges on using a book all about the Three Mothers as a MacGuffin.
Tenebrarum founded her home in New York City, in an apartment complex, back in 1910. As the mother of darkness, she is both the youngest and cruelest of the bunch. In Inferno, she uses the bulk of her powers for the purposes of deception. She spends the majority of the runtime pretending to be the innocent nurse of Professor Arnold, when in fact she is using him as her slave.
Her other focus is attempting to stop people from reading the Three Mothers book, through any means necessary. It is even revealed that Professor Arnold is actually a man named Varelli, who wrote the book on the Three Mothers and has been suffering in servitude ever since.