1. While on set of The Exorcist, director William Friedkin would have the prop man randomly fire shotgun blanks to surprise the actors.
2. The late H.R. Giger was responsible for all of the creature designs in Alien. He incorporated a real human skull into the head of the alien.
3. Walnuts and dead chickens were used to create the gory noises heard in The Evil Dead.
4. Scream was inspired by actual events that took place in Gainesville, Florida, during the early '90s.
5. Linda Blair, who is best known for playing the possessed child Regan in The Exorcist, had a small cameo in Scream.
6. Iconic late horror director Wes Craven also had a cameo.
7. Due to the marketing around The Blair Witch Project, some people were convinced that actor Heather Donahue was actually dead and sent her mother sympathy cards.
8. The Blair Witch actors all agreed to stay in character while filming, but if they needed a time out or wanted to comment on something, they would use the code word "taco".
10. Michael Cera auditioned for the role of Cole in The Sixth Sense.
He didn't know it was about dead people so he was upbeat and optimistic in his audition.
11. M. Night Shyamalan comes from a family full of physicians. He was expected to become one too, but instead he fell in love with film at an early age.
12. Saw was inspired by a news story.
13. The iconic puppet from Saw, known as Billy, was so precious to filmmakers James Wan and Leigh Whannell that they paid for it to have its own seat on a flight from Melbourne to Los Angeles.
14. The original wooden puppet was also handmade by Wan.
15. Billy has also popped up in movies other than Saw. He was briefly shown as an Easter egg in Insidious, Dead Silence, and Death Sentence.
16. Wolf Creek is a real place. It's located in Western Australia and is actually known as Wolfe Creek.
17. John Jarratt, who played serial killer Mick Taylor way too convincingly, actually used to be the host of Australian lifestyle show Better Homes and Gardens.
18. Paranormal Activity director and writer Oren Peli filmed the movie in his own home. Despite its ~scary~ reputation, Peli later had no issues selling the house.
19. The doll from The Conjuring and its spinoff, Annabelle, is based on a real-life doll that looks very different. The real Annabelle is just a regular Raggedy Ann Doll.
20. Eli Roth's cannibal film The Green Inferno was shot in a remote village in the Amazon. It took five hours of travel every day in Land Rovers plus 90 minutes up a river to access the location.
21. In fact, it was so remote that the locals had never seen a film before. The producers showed them Cannibal Holocaust, which they thought was a comedy and "the funniest thing they'd ever seen".
22. Actress Lorenza Izzo almost died while filming The Green Inferno. She was thrown into a river with a rock to cling on to, but the water pulled her under and she almost drowned.
23. And Roth, who is also the man behind Hostel and Cabin Fever, has previously stated that the best way to make gory scenes more realistic is to use fruit, saying: "A grape makes an amazing eyeball when photographed at the right angle."
24. It Follows director David Robert Mitchell didn't actually pitch the movie. Instead he made an elaborate lookbook because he believed the concept for the film was "so silly" that he "avoided saying it out loud".
25. And although the movie has an '80s vibe, it actually doesn't fit into any time period. The film deliberately keeps you guessing about the era it's in because it's placed outside of time.
26. The Babadook was inspired by a strange story writer/director Jennifer Kent heard in the early '00s.
27. And years after the release of the movie in 2014, the monster in the film has bizarrely now become a queer icon online.
28. The Witch director Robert Eggers revealed it bothers him that you can see Anya Taylor-Joy's earring holes in the film. He said in the DVD commentary that he wished he had CG'd them out.
29. Joaquin Phoenix was originally meant to star in Split before James McAvoy was cast.
Phoenix previously worked with Split director M. Night Shyamalan on two of his other films, The Village and Signs.