It's time for some good, old-fashioned blood and gore!
This is the 1977 Italian film Suspiria directed by noted horror film director Dario Argento. It's the first in a thematic trilogy Argenta calls "The Three Mothers," which was followed by Inferno and The Mother of Tears.
The plot is this: Suzy Banyon (Jessica Harper) is an American ballet student who has moved to Germany to go to a prestigious ballet school. The school, however, is creepy and is associated with several deaths, including that of a former student. The school is run by Madame Blance and Miss Tanner, while Suzy befriends the blind pianist Daniel and her roommate Sarah.
The true horror in Suspiria is not in the plot, however. It's in the cruel and inventive ways of dying: the very first death (in the opening sequence) has the ex-student being smothered, stabbed, graphically disemboweled, and then hung on a cord for a skylight (where the broken glass ends up falling and killing someone else). In another scene, a character tries to escape through an open window and ends up falling into a room filled with barbed wired. Why is there a room with nothing but barbed wired? There's no explanation, just the eerie atmosphere of the film.
The ending is a bit rushed and kind of lame, I will give you. The Big Bad is dispatched so easily it seems like a cheat. But the rest of the film is beautifully shot pain, with every murder lovingly detailed. It's an ode to suspense and death by Dario Argento and if you enjoy horror films, you should see it at least once.