A brilliant but deranged neurosurgeon becomes obsessively fixated on a judge's daughter. With the help of an escaped criminal whose face he has surgically deformed, the mad man lures her, her father, and her fiancé to his isolated castle-like home, where he has created a torture chamber with the intent of torturing them for having 'tortured' him.
University professor George Kingsley is struck by gangsters while crossing the street, leaving him with brain damage and one of the gangsters, Cannon, paralyzed. Kingsley's friend Dr. Sovac attends to both men, and when Cannon offers him a reward for aiding his recovery, Kovac transplants part of Cannon's brain into the dying Kingsley's skull, creating a dual personality.
An obsessed scientist conducts profane experiments in evolution, eventually establishing himself as the self-styled demigod to a race of mutated, half-human abominations.
Tampering with life and death, Henry Frankenstein pieces together salvaged body parts to bring a human monster to life; the mad scientist's dreams are shattered by his creation's violent rage as the monster awakens to a world in which he is unwelcome.
A mad scientist creates a monster called "Mosaico," who breaks out of the laboratory to hunt down and kill beautiful women.
Confined to a mental hospital, young Kirsty Cotton insists her supposedly dead father is stuck in hell, controlled by sadomasochistic demons after being betrayed by his evil, occult-obsessed wife, Julia. Few believe Kirsty, except the thrill-seeking Dr. Channard, who is intrigued by the young woman's lurid stories. So when Kirsty and fellow patient Tiffany head to hell for a rescue, Channard and Julia are close behind.
After Malukan immigrants engage in a string of corpse mutilations at various New York City hospitals, a doctor and a morgue assistant travel to the Maluku Islands to investigate.
Having escaped from the psychiatric prison, Dr. Albert Beck hides out in an empty house until its new owners unexpectedly arrive to move in! Forced into the attic to evade the recently widowed mother, Beck watches from above... undeniably attracted to her 18-year-old daughter.
A psychologist snaps, becomes a vigilante and wipes out inner city "scum." Occasionally he kidnaps bad girls and hookers and and hunts them for sport Most Dangerous Game style.
After a pawn shop robbery goes askew, two criminals take refuge at a remote farmhouse to try to let the heat die down, but find something much more menacing.
Professor Frankenstein creates a teenager from an accident victim, who gets angry when he learns he is going to be taken apart.
The eminent Dr. Phibes awakens from a decade of suspended animation and heads to Egypt with the corpse of his dead wife, which he intends to resurrect by murdering people in strange and heinous ways.
Dr. Bill Cortner and his fiancée, Jan Compton, are driving to his lab when they get into a horrible car accident. Compton is decapitated. But Cortner is not fazed by this seemingly insurmountable hurdle. His expertise is in transplants, and he is excited to perform the first head transplant. Keeping Compton's head alive in his lab, Cortner plans the groundbreaking yet unorthodox surgery. First, however, he needs a body.
Chaney plays two roles: mad scientist Arthur Lamb and Lamb's "experiment", known only as the Ape Man. This hideous creature was the result of Lamb's attempts to transplant animal glands into human beings. A lost film.
Murders, with victims dying from spines broken by brute strength, erupt in the city and the killers, when encountered, walk away unharmed by police bullets which strike them. A police doctor's investigation of the deaths leads to the discovery of an army of dead criminal musclemen restored to life, remotely controlled by a vengeful former crime boss and a former Nazi scientist, from the latter's laboratory hidden in the suburbs.
Dr. Henry Jekyll is a well-regarded physician whose evenings are spent researching a rare and sacred Amazonian flower so potent it's said to literally separate the soul, giving life to man's Dark Self. The obsessive experiments to isolate its psychotropic properties happen to coincide with a series of brutal murders gripping the city with fear. Jekyll knows it's no coincidence. While his nights are lost to him, he awakens with bloody mementos and violent memories of the screams of his victims.
A fugitive doctor tries to raise the dead for South Sea Islanders.
A mad scientist creates man eating creatures from carnivorous plants.
Dr. Bernard Adrian is a kindly scientist who seeks to cure a young woman's polio. He needs human spinal fluid to complete the formula for his experimental serum. Meanwhile, a vicious circus ape has broken out of its cage, and is terrorizing the townspeople. Can there be a connection?
Following his forced retirement from an appalling rock band, Jason decides to vacation at Brittlehouse Manor, a health farm run by the leather-gloved, ex-Nazi scientist Dr. Storm. Along the way, Jason meets Judy, also on her way to Brittlehouse Manor to visit her aunt, who married Dr. Storm some years ago. Once they arrive, the pair realise rather quickly that something is wrong, probably because the other guests have had their brains surgically removed, or all the blood pouring from the sink, or possibly just because the creepy midget keeps telling them to brush their teeth.