1. Psycho was based on a novel which was loosely inspired by a murderer and necrophile, by the name of Ed Gein.
2. It was the first American film to show a toilet on-screen.
3. And it was also Hitchcock's most financially successful film, grossing $32 million during its first theatrical release.
4. To preserve the secrecy of the film's ending, Hitchcock bought all the available copies of the novel it was based on.
5. And he enforced a rule that theatre companies had to restrict access to latecomers, once the movie had started.
6. The dialogue of Norma Bates was provided by three separate actors, including one man, whose voices were blended together by sound recordists.
7. The shower murder scene contained over 77 different camera angles and 50 cuts.
8. And the fake blood in the scene was actually chocolate syrup, which shows up better on black-and-white film.
9. Grace Kelly turned down the lead in On The Waterfront to star in Rear Window.
10. And it's the only film in which Kelly is seen with a cigarette. In other films she had refused to smoke on screen.
11. All of the sound in the film is diegetic, meaning that all the music, speech, and other sounds (besides the orchestral piece heard in the beginning) come from within the film's world.
12. The entire movie was shot on one set which, at the time, was the largest indoor set ever built at Paramount studios.
13. Ross Bagdasarian, who played "The Songwriter", was also one in real life. He went on to make Alvin and the Chipmunks.
14. Hitchcock got revenge on a producer he hated by modelling the villain's mannerisms and appearance on them.
16. And Hitchcock believed this was because James Stewart, who was 50 years old at the time, was too old to convincingly play 25-year-old Kim Novak's love interest.
17. According to associate producer Herbert Coleman, an uncredited second unit cameraman by the name of Irwin Roberts was responsible for the film's famous "vertigo shot" camera technique.
18. The production went through several title options including A Matter of Fact, The Mad Carlotta, Face in the Shadow, Possessed by a Stranger, and Darkling I Listen.
19. As part of a marketing campaign, Paramount leaked rumours of an on-screen feud between Novak and Hitchcock. Novak later stated, however, that "nothing could be further from the truth".
20. Dial M For Murder is Hitchcock's only film to be entirely shot in 3-D.
21. And because of the cumbersome 3-D camera process, Hitchcock commissioned the construction of an enormous, four-foot tall prop telephone and giant fake finger to be used for specific closeup shots.
22. The film was based on a stage play by Frederick Knott, which premiered as a BBC TV special in 1952. The rights were later sold to Warner Bros. for $75,000.
23. Margot's psychological condition is portrayed by her changing wardrobe. In the beginning she wears bright colours suggesting a happy life, but as the film grows darker, so too does her wardrobe.
24. In total, 25,000 birds were used in the production of The Birds, including 3,000 birds that were specially trained by animal handler Ray Berwick.
25. To film the intense bedroom scene where Tippi Hedren's character is attacked, the animal handlers pelted live birds at her to give the sequence a more manic feel.
26. Live birds were also attached to Hedren's clothing, which resulted in her being hospitalised for a week after suffering an injury to her eye.
28. It is the only one of Hitchcock's films not to have a "The End" card. According to the director, it was purposely left out to give the story a feeling of unending terror.
29. Although Hitchcock is well-known for his cameos, his two dogs, Stanley and Geoffrey, also make an appearance.
31. The film was shot in 10 takes ranging from four-and-a-half to just over ten minutes in duration. This was because Hitchcock envisioned the final picture to look like a continuous reel of footage.
32. Along with The Man Who Knew Too Much, Rear Window, The Trouble With Harry, and Vertigo, the movie was unavailable for decades because ownership of these titles later reverted back to Hitchcock. The movies were re-released around 1984 after a 30-year absence.
33. North by Northwest was conceived while screenwriter Ernest Lehman and Hitchcock were supposed to be adapting the novel The Wreck of the Mary Deare.
34. The shot of Cary Grant walking into the United Nations building was filmed in secret. Officials at the UN denied the request for filming on the property, so instead Hitchcock hid a camera in a nondescript truck and filmed from across the street.
35. One line of dialogue from Grant and Eva Marie Saint's first meeting on the train was censored for its theatrical release. She originally says, "I never make love on an empty stomach" and it was dubbed over as "I never discuss love on an empty stomach".