Movie monsters have been through an evolution as wild and nuanced as Charles Darwin’s. Back in the days of silent film, they were created with paint and fish gills. Studios eventually graduated to puppets and monkey models, before CGI made it impossibly easy to dream up new terrors. Because it’s almost Halloween and you’re likely watching one of those monsters—whether it’s Frankenstein, Dracula, or The Fly—on TV, here are the secrets behind their creation. If you think they’re scary, you should’ve seen Lon Chaney’s nose on The Phantom of the Opera set.

1. THE PHANTOM OF THE OPERA (1925)

Lon Chaney, Sr. introduced American moviegoers to Erik, a.k.a. the Phantom of the Opera, in his 1925 silent film. Chaney had previously portrayed Quasimodo in The Hunchback of Notre Dame and was already famous for doing his own make-up. Although he was quite secretive about his methods, most of his Phantom tricks have been revealed. For the exaggerated cheekbones, he used a combination of cotton and collodion. He accentuated his nostrils with black paint, and liberally applied dark eyeliner. Chaney also popped a serrated set of false teeth into his mouth. But the weirdest stuff concerned his nose: To contort it, Chaney attached a strip of fish skin and then poked himself with wires. As you might imagine, this wasn’t a pleasant experience. “Sometimes it would bleed like hell,” cinematographer Charles Van Enger told the Los Angeles Times. “We never stopped shooting. He would suffer for it.”

2. DRACULA (1931)

Prior to playing Count Dracula in the 1931 classic, Bela Lugosi starred in a 1927 Broadway play about the famous bloodsucker. The show was such a success that Hollywood decided to adapt it for the silver screen, and although producers were hesitant to cast an unknown Hungarian actor in the title role, Lugosi supporters successfully lobbied on his behalf.

Lugosi reportedly insisted on applying his own make-up for the film, as he did on the stage. He refused to wear the fangs Universal wanted, but agreed to a hairpiece that would add a widow’s peak to his “somewhat thinning hairline.” Some also speculate that the medallion Dracula wears was Lugosi’s own personal possession. It was clearly important to him; he was allegedly buried in a version of it when he died in 1956.

3. FRANKENSTEIN (1931)

Jack Pierce is something of a legend in monster movie lore. The make-up artist was responsible for fixing the faces of the Mummy and Wolf Man, but one of his earliest hits was the 1931 horror flick Frankenstein. Pierce made Boris Karloff into the mutant by smearing green greasepaint all over his face. Karloff’s fingernails were painted black, and his eyelids were stiffened. Pierce gave him a flattop head with a combination of cotton and gum. Then the costume department got to work making the 5’11” Karloff into a looming terror. Karloff was given platform boots, each one weighing about 13 pounds, as well as a jacket that was too short and a doubled set of pants. The camera crew went the extra mile by filming Karloff at a low angle, so he looked all the more intimidating.

4. THE MUMMY (1932)

Karloff and Pierce quickly re-teamed for 1932’s The Mummy. In this outing, Pierce had a painstaking process for layering on Karloff’s bandages: As Pierce explained, “The complete makeup, from the top of his head to the bottom of his feet, took eight hours. The bandages on his body had to be put on. Then I had to seal them with tape so they wouldn't unravel. Then after that, I had to put the burned bandages on. After that I put the clay on. It was an hour and a half to take it off.”

Pierce also had to pin back Karloff’s ears and eyes, smash clay into his hair, and affix a decaying nose to his face. No wonder the actor called it “the most trying ordeal I have ever endured.”

5. KING KONG (1933)

The two men behind King Kong were Merian C. Cooper and Ernest B. Schoedsack, a pair with a taste for adventure. Prior to Kong, the friends had crossed frozen mountains to film a nomadic tribe and shot in the jungles of (then) Siam. They wanted to make a documentary about gorillas next, but producer David O. Selznick asked them to do a fictional ape feature instead.

After abandoning their initial plan—to get a gorilla and Komodo dragons and just roll—the pair tapped stop-motion expert Willis O’Brien. He’d created the dinosaurs in 1925’s The Lost World, so he was just the man for the job. O’Brien applied his movie magic to an 18-inch model of Kong sculpted by Marcel Delgado. He also built a full-sized monkey hand and a full-sized head to complete the illusion. Along with those cinematic sleights of hand, the movie featured ground-breaking use of miniature rear projection.

6. CREATURE FROM THE BLACK LAGOON (1954)

In this case, the details of the creature’s costume aren’t the most compelling angle. Yes, it sprang from a Citizen Kane dinner party conversation about half-reptilian men in the Amazon. And yes, the Oscar served as the earliest model for the Gill-Man. But the fight between Millicent Patrick and Bud Westmore for ownership is way more interesting.

Patrick was a rising star in the Universal movie monster machine. Previously, she had worked on It Came from Outer Space and Abbott and Costello Meet Dr. Jekyll and Mr. Hyde as a sketch artist and mask maker, respectively. She was tapped next for Creature for the Black Lagoon and once the movie was released, she was sent on tour to publicize it. This pissed off Westmore. He was part of the famed Westmore family of make-up artists and also part of the Creature from the Black Lagoon make-up team. He was not happy that Patrick was being billed as “the Beauty Who Created the Beast,” and said so in several formal complaints to the Universal execs. Those execs thought he was being a big baby, but Westmore made good on his threat to never employ her again and effectively ended her career. He also told everyone he’d made the Gill-Man costume Patrick designed for years. What a monster.

7. GODZILLA (1954)

Public Domain, Wikimedia Commons

Godzilla has appeared in a whopping 30 movies, but the first was the 1954 Japanese film Gojira—and it came from a horrible, true-life incident. In March of 1954, the crew of the fishing boat Daigo Fukuryū Maru (or Lucky Dragon 5) was exposed to radiation, thanks to the secret hydrogen bomb tests America was conducting on Bikini Atoll. The Japanese were outraged and terrified. So producer Tomoyuki Tanaka tapped into those fears with his opening Gojira sequence, in which a peaceful boat crew is besieged.

Only they were being attacked by Godzilla, the stand-in for nuclear threats. Tanaka wanted to create a monster movie in the vein of King Kong and The Beast from 20,000 Fathoms. To execute this vision, he assembled director Ishirō Honda and special effects wiz Eiji Tsuburaya. Tsuburaya outfitted one of his technicians with a latex dinosaur suit featuring bamboo spars. In order to convey the monster’s forceful stomps, he shot the Godzilla scenes at double the speed and then slowed them down. Although this technique became mocked later down the line, Tsuburaya’s work (in conjunction with Honda, Tanaka, and all the rest) terrified Japanese moviegoers. "In producing Gojira, [they] accomplished a feat unequaled at the time,” Godzilla expert John Rocco Roberto wrote. “In the guise of a typical Hollywood-style ‘monster movie,’ they made Japan, and ultimately the world, experience the bombings of Hiroshima and Nagasaki all over again."

8. ALIEN (1979)

The alien that terrorizes Ellen Ripley came from the designs of H.R. Giger. The surrealist was chosen to design the movie’s ETs after working with screenwriter Dan O’Bannon on a failed adaptation of Dune. His haunting art came to life with the help of condoms (used on the creature’s lips) and bones—Giger even fit a real human skull into the tip of the monster’s head. Once the final product was complete, Ridley Scott hired a 6’10” Nigerian art student named Bolaji Badejo to play the alien. Because his tail was so ungainly, Badejo had to sit on a custom swing between takes.

9. AN AMERICAN WEREWOLF IN LONDON (1981)

Legendary makeup artist Rick Baker got his first Academy Award for transforming actor David Naughton into a hairy hound. Baker and director John Landis had very specific ideas about the werewolf transformation: they didn’t want to do the gradual dissolves used in old monster movies; they wanted to show the pain and movement of a body in metamorphosis. While shooting the big scene, Baker applied the full wolf fur to Naughton first, let the crew film it, and then trimmed it back to shoot earlier stages of the transformation. He also came up with “change-o-heads” and “change-o-hands,” which were fake hands and heads with mechanisms inside that stretched and distorted the props to fit the transformation. Clearly Baker had a lot of creative freedom on the set, but he did lose at least one argument: he wasn’t allowed to make the wolf two-legged.

10. THE FLY (1986)

David Cronenberg’s 1986 remake of The Fly arrived just five years after An American Werewolf in London. But Baker’s pioneering techniques were by that point so well-known that The Fly creature effects artist Chris Walas was determined to do something different. For the early stages of scientist Seth Brundle’s transformation, Walas applied elaborate prosthetics and make-up to Jeff Goldblum’s face and body. Each application could take up to five hours, and Goldblum was apparently not an easy canvas. For the later stages of the metamorphosis, Walas oversaw a fleet of puppets, rigs, and dollies that constituted the “fly.” Plates and springs inside the creature’s head facilitated the moment when Veronica accidentally tears its jaw. It was all pretty intricate stuff, but in the end, the work paid off. Walas took home the gold for his grotesque puppetry at the 1987 Academy Awards.