The Revenge of Dr. X

Stefan learns that his invalid grandmother was the nurse/lover of Nazi doctor Franz Kindler and that she removed his brain when the Nazis were losing WW2. Unable to successfully perform a transplant on test subjects, she needs Stefan to carry on for her now that her health is failing.

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.

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.

A mad scientist creates a monster called "Mosaico," who breaks out of the laboratory to hunt down and kill beautiful women.

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.

Professor Frankenstein creates a teenager from an accident victim, who gets angry when he learns he is going to be taken apart.

A plastic surgeon goes mad when he discovers that his wife have an affair. He fakes her death and disfigure her and locks her in the cellar.

After having a feud with director Kenneth J. Hall, producer Fred Olen Ray hired Ted Newsom to shoot brand new footage (on video) to weave in with scenes from Hall's film Evil Spawn (1987).

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.

Seymour works in a skid row florist shop and is in love with his beautiful co-worker, Audrey. He creates a new plant that not only talks but cannot survive without human flesh and blood.

As Zac’s relationship with his long suffering girlfriend deteriorates, a mysterious ‘plant’ is discovered in his back yard.

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.

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.

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.

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.