The Living Brain That Came From Outer Space

I invite you to help me compile a list of intelligent science fiction and/or fantasy films. Four spring immediately to mind — Robert's Wise's 1951 film "The Day the Earth Stood Still," the 1966 Francois Truffaut film "Fahrenheit 451," the 1967 Hammer film "Five Million Years to Earth" (a/k/a "Quatermass and the Pit"), based on a BBC serial of the 1950s, and the 1980 film "Altered States," Paddy Chayefsky's philosophical monster movie.
Any other candidates?