In the sequence shown, Dakota Johnson’s character performed a ballet routine under the guidance of a teacher played by Doctor Strange’s Tilda Swinton.
In the scene, we saw that another dancer in another area began to mimic the movements made by Johnson’s character, contorting and twisting in bizarre ways as Johnson danced.
Dakota Johnson’s remarks about the disturbing nature of Suspiria also make quite a bit of sense when we consider the gruesome material that will appear in the film.
By the end of the scene (which was shown during a lunch event at CinemaCon, no less) Johnson’s dancing eventually killed the other dancer and quite literally tore her apart.