Psycho/Trivia

Black Sheep Hit: The original book was this for Robert Bloch, most of whose horror fiction involved the Cthulhu Mythos.
Directed by Cast Member: Anthony Perkins directed the third movie.
Doing It for the Art: Hitchcock went to a lot of trouble to try and avoid the film's twists being revealed. Most notably, he went about buying up copies of the source novel out of his own pocket.
Enforced Method Acting: Hitchcock allowed both Perkins and Leigh to improvise their roles as long as it didn't involve moving the camera. Norman's habit of munching candy is an example. Same goes for Janet Leigh.
Genre Killer: Many film historians consider Psycho to the be movie that killed Film Noir, as the purpose of the first hour or so is to continuously set up and avert the tropes of that genre.
Hey, It's That Guy!: Mr. Cassidy is Sam Wainwright. California Charlie is MacGyver's grandfather. And the psychiatrist is Kolchak's boss--or Lieutenant Shrank.
- Look closely after the psychiatrist scene, when the cop takes the blanket to Norman. See the other, non-speaking cop who's standing guard outside the door? It's a young Ted Baxter!
Real Life Relative: The brief appearance by young Norman in Psycho II was Anthony Perkin's son, Oz.
Throw It In: Location shooting (for the scene where Marion drives out of town with the money) was done in downtown Phoenix in December 1959. After Christmas decorations were discovered to be visible in the footage, a graphic was added to the beginning of the film setting the date as "Friday, December the Eleventh".
- Also, Norman's Character Tic of eating candy was a suggestion of Perkins's that Hitchcock happened to like
What Could Have Been: Hitchcock originally wanted the shower scene to play without music, but Herrmann begged him to try it. Yes, the Trope Maker for Psycho Strings very nearly didn't come about at all.