Monsters were not always monsters. Just like every superhero has their own origin story, monsters are born from the unlikeliest of places and situations. Once they are alive and animated, their carnivorous crusades are trapped in a mindless vessel. They must endlessly pursue its prey to tame the beast inside of them. Escape can be found; the hex can be lifted, but only with the utmost belief and meticulous procedures.

Innocents have little precious time to figure out the reversal process or kill switch to the maddening monster mayhem. Friends become foes, snap decisions become slippery slopes, and men become monsters. The kismet killers transform into obelisks of terror, warning witnesses to look no further less they too fall wayside to fear and horror. Transformations that make puberty look tame and mortals insane, going through these corporeal changes is never an easy sight to behold or become.

8 Frankenstein (1931)

     Universal Pictures  

Scientists are not the only ones that make mistakes. Dr. Henry Frankenstein’s Monster (Boris Karloff) was born from a series of grave-robbed cadavers and a confiscated brain. His hunchback assistant and accomplice, Fritz snatched the latter from Henry’s university. He initially grabbed a normal brain, but damaged its contents, so he stole the brain that belonged to a criminal instead. In a metaphysical personality transplant, the live-action board game Operation took place with electrifying results. Playing God by invoking the laws of nature and bending them to your will was a lofty goal with lowly consequences.

7 Dr. Jekyll and Mr. Hyde (1932)

     Paramount Pictures  

Academy Award-winner for Best Actor Fredric March plays Doctor Jekyll who discovers a formula for releasing one’s inner demons. He takes on the form of Mr. Edward Hyde, an immoral and violent alter ego. The possessed doctor was an early Two-Face, capable of inflicting the unchecked darker nature of man’s duality. A chemical concoction seems like a cop-out, but the transformation is a homely sight that skirts the line between inhibitions and malpractice.

6 The Wolf Man (1941)

Lon Chaney Jr. played the Wolf Man in four future sequels after the success of his lupine debut. Before he turns, Chaney Jr. was Larry Talbot, who grew smitten with antique store owner, Gwen Conliffe (Evelyn Ankers) in his home country of Wales. He buys a silver cane topped with the head of a wolf and marked with a pentagram. Gwen and the villagers are privy to the legendary beast, often reciting its famous verse: “Even a man who is pure in heart, and says his prayers by night; May become a wolf when the wolfsbane blooms and the autumn moon is bright.” The supernatural dogma of the townspeople, matched with the superstitious artifacts and inevitable doom makes this werewolf insatiable as his gaze on a full moon.

5 Cat People (1982)

An erotic horror that will curl your tail, Cat People is a modernized version of the self-titled 1942 classic. Instead of werewolves, there are werecats who must kill humans to reassume their human form. The carnal tensions and predatory brutality run high as a separated family must cope with their feline origins. The effect is maladaptive as intended, with the female lead’s grotesque skin turning into a black panther coat. Nothing can curtail this ferocious fräulein feline except bestiality. It’s the Beauty and the Beast remake Disney Adults could never imagineer!

4 The Toxic Avenger (1984)

     Troma Entertainment  

New Jersey’s first superhero was a true-blue nerd named Melvin Ferd Junko III from the fictional town of Tromaville. With possibly the world’s nerdiest name, tragedy had to befall our unlikely hero. Sadists everywhere rejoiced when Melvin’s bullies harass him out a second story window and land in a barrel of toxic waste. He runs to take a bath that turns into a boiling caldron. His muscles pulsate and blister, his hair falls out, and the whimpering Melvin is replaced by the lumpy, lumbering, Toxic Avenger!

3 An American Werewolf in London (1981)

Teen Wolf (1985) can howl his heart out! John Landis, director of Schlock (1973) and National Lampoon’s Animal House (1978), struck the balance between horror and comedy. After Landis’ script laid dormant for a decade, David Kessler (David Naughton) finds himself attacked by a werewolf hiking one night in England. He survives, but his friend perishes, only appearing to him as premonitions where he warns David of the werewolf’s curse. When a full moon catches David’s eyes, the transformation commences with bone-breaking body horror.

2 The Fly (1986)

     20th Century Fox  

David Cronenberg ups the ante in body horror with his remake of The Fly (1958). Seth Brundle is played by Jeff Goldblum, a devoted but over-his-head scientist. He experiments with a teleportation device in order to instantaneously transport living organisms from one location to another. He succeeds and decides to teleport himself, unknowingly teleporting a housefly with him. The greatest freak accident known to mankind ensues, turning him into a freak of nature. The biological anomaly is proof that science, with all its progressive benefits, can go too far in the wrong direction or carry detractions.

1 The Thing (1982)

John Carpenter takes body horror and monster transformation to its perverse peak. In this remake of The Thing from Another World (1951), the plant-based monster from the original becomes a parasitic host for a team of American researchers in Antarctica. It assumes the identity of its flesh puppets, undetected until it rears its ugly, crustaceous, mangled forms. It’s enough to make H.P. Lovecraft wince.