Entertainment Weekly online currently features an essay that looks back at the mystique of Psycho in light of the new film Hitchcock. The essay includes this gem:

Why it really is about the death of God. Like just about all the greatest movies, Psycho works on the level of myth. It starts out as a faintly chintzy morality play in which Marion Crane, though she made a big mistake, will presumably be chastened, redeemed, protected, and rewarded by a universe that saves those who save themselves. It turns into a movie in which no one — not even a sinner who repents — will be saved. And that, for the first time in Hollywood, is a truly godless world. Psycho cleaves the 20th century in half: It turns order into madness, ushering us into a new way of seeing, of being.