A mad doctor uses a fake taxi driver to kidnap victims and then removes their eyes in hopes of perfecting an eye transplant that will allow his blind wife to see again. One of the doctor's servants ends up getting possessed by not one, but several of the victims.
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.
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.
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.
After a team of surgeons botches his beloved wife's operation, the distraught Dr. Phibes unleashes a score of Old-Testament atrocities on his enemies.
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.
The doctor is back! And this time, she’s cloned herself to make an army of unstoppable warriors!
An unnamed doctor has always had everything he's ever wanted, but that has only made him develop more extreme and depraved needs. He kidnaps a young couple in the prime of their life together and forces them into a game of torment that slowly extinguishes their hopes for survival.
An insane surgeon's obsession with an actress leads him to replace her wounded pianist husband's hands with the hands of a knife murderer--hands which still have the urge to throw knives.
Dr. Leon Kravaal develops a potential cure for cancer, which involves freezing the patient. But an experiment goes awry when authorities believe Kravaal has killed a patient. Kravaal freezes the officials, along with himself. Years later, they are discovered and revived in hopes that Kravaal can indeed complete his cure. But human greed and weakness compound to disrupt the project.
A mad doctor (Bela Lugosi) and his helpers (John Carradine, George Zucco) lure girls to his lab for brain work, to help his wife.
A fugitive, dangerous madman reaches an English village where he confronts his former partner who left him for dead in the jungle after their discovery of a diamond mine. When the former partner also claims to have since lost the mine and all its wealth, which he took all for himself, and though the partmer is still living in a state of luxury , the madman takes up an offer from a crazed scientist to make him invisible, something the scientist has already done with experimental animals, so that he can take revenge.
In 19th century England, a noted brain surgeon rescues a former student from being hanged on a false conviction for murder, and spirits him away to an ancient, repurposed abbey far in the countryside. There, he connives his pupil into assisting him in mapping the functions of the various parts of the human brain, using living subjects who are under a terrible animation-suspending drug called "black sleep". Subsequently, the student, along with the daughter of one of the subjects, discover that most of these subjects have survived but are being kept in a dungeon-like cellar, in various stages of physical and mental derangement...
Dr. Bonner plans to live forever through periodic gland transplants from younger, healthier human victims. Bonner looks about 40; he's really 104 years old. But people are starting to get suspicious, and he may not make 200.
An ex-vaudeville actor is working as the assistant to a doctor who has Frankenstein aspirations. The ex-vaudeville actor kills the doctor and decides to assume the identity of the dead physician.
Dr. Hohner, theatre physician at the Vienna Royal Theatre, murders his mistress, the star soprano when his jealousy drives him to the point of mad obsession. Ten years later, another young singer reminds Hohner of the late diva and his old mania kicks in. Hohner wants to prevent her from singing for anyone but him, even if it means silencing her forever.
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.
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?
A mad scientist creates man eating creatures from carnivorous plants.
A fugitive doctor tries to raise the dead for South Sea Islanders.