Alraune

Alraune is a 1928 German horror film starring Paul Wegener. It is based on a book written in 1911 that is in turn "rooted" in German folklore.

from The New York Times review from the time of the film's release: "If you like this sort of thing you'll find it a superior product. ... A most engaging evening's display of erotics."

Fright.com says,

This German silent is the most famous of the many adaptations of Hanns Heinz Ewers’ ALRAUNE, and with good reason. The film’s chilly atmosphere, perverse storyline and stunning lead performance by the incomparable Brigitte Helm make for a unique and impacting viewing experience.