Both of these elements work because Hitchcock devotes his full attention and skill to treating them as if they will be developed for the entire picture.
These surprises are now widely known, and yet “Psycho” continues to work as a frightening, insinuating thriller. That’s largely because of Hitchcock’s artistry in two areas that are not as obvious: The setup of the Marion Crane story, and the relationship between Marion and Norman ( Anthony Perkins). Both of these elements work because Hitchcock devotes his full attention and skill to treating them as if they will be developed for the entire picture.