Characterization
The character Norman Bates in Psycho was loosely based on two people. First was the real-life serial killer Ed Gein, about whom Bloch later wrote a fictionalised account, "The Shambles of Ed Gein", in 1962. (The story can be found in Crimes and Punishments: The Lost Bloch, Volume 3). Second, it has been indicated by several people, including Noel Carter (wife of Lin Carter) and Chris Steinbrunner, as well as allegedly by Bloch himself, that Norman Bates was partly based on Calvin Beck, publisher of Castle of Frankenstein.
The characterization of Bates in the novel and the movie differ in some key areas. In the novel, Bates is in his mid-to-late 40s, short, overweight and homely. In the movie, he is in his early-to-mid-20s, tall, slender, and handsome. Reportedly, when working on the film, Hitchcock decided that he wanted audiences to be able to sympathize with Bates and genuinely like the character, so he made him more of a "boy next door." In the novel, Bates becomes "Mother" after getting drunk and passing out; in the movie, he remains sober before switching personalities. Finally, in the novel Mary Crane is "Mother"'s first victim, whereas in the film and its sequels, it is revealed that "Mother" had killed twice before.
In the novel, Bates is well-read in occult and esoteric authors such as P.D. Ouspensky and Aleister Crowley. He is aware that "Mother" disapproves of these authors as being against religion.
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