In foggy London Dr Jekyll experiments on newly deceased women determined to discover an elixir for immortal life. Success enables his spectacular transformation into the beautiful but psychotic Sister Hyde who stalks the dark alleys of Whitechapel for young, innocent, female victims, ensuring continuation of the bloodstained research. With each transformation Sister Hyde becomes the more dominant personality, determined to eventually suppress the frail, ineffectual Dr Jekyll forever.
While dabbling in Satanism, Count Karstein resurrects Mircalla Karnstein who initiates him into vampirism. As a rash of deaths afflicts the village, Gustav the head of Puritan group leads his men to seek out and destroy the pestilence. One of his twin nieces has become inflicted with the witchcraft but Gustav's zeal and venom has trapped the innocent Maria, threatening her with a tortuous execution, whilst Frieda remains free to continue her orgy of evil.
An elderly heiress is killed by her husband who wants control of her fortunes. What ensues is an all-out murder spree as relatives and friends attempt to reduce the inheritance playing field, complicated by some teenagers who decide to camp out in a dilapidated building on the estate.
Count Yorga continues to prey on the local community while living by a nearby orphanage. He also intends to take a new wife, while feeding his bevy of female vampires.
A social misfit, Willard is made fun of by his co-workers, and squeezed out of the company started by his deceased father by his boss. His only friends are a couple of rats he raised at home, Ben and Socrates. However, when one of them is killed at work, he goes on a rampage using his rats to attack those who have been tormenting him.
In Paris, in the beginning of the Twentieth Century, Cesar Charron owns a theater at the Rue Morgue where he performs the play "Murders in the Rue Morgue" with his wife Madeleine Charron, who has dreadful nightmares. When there are several murders by acid of people connected to Cesar, the prime suspect of Inspector Vidocq would be Cesar's former partner Rene Marot. But Marot murdered Madeleine's mother many years ago and committed suicide immediately after.
An American actress inherits a castle in Transylvania. What she doesn't know is that her ancestor, the Baroness Catali, was in actuality a vampire countess, and emerges from her tomb to ravage the nearby village and Catholic seminary.
A playboy adventure novelist joins his publisher on an expedition to Voodoo Island in the Caribbean, where a cancer researcher is being forced to turn the tribes-people into zombies.
Dr. Roger Girard is a rich scientist conducting experiments on head transplantation. His caretaker has a son, Danny, who, although fully grown, has the mind of child. One day an escaped psycho-killer invades Girard's home, killing Danny's father before being gunned down himself. With the maniac dying and Danny deeply unsettled by his father's death, Dr. Girard decides to take the final step and transplant the killer's head onto Danny's body.
After her prostitute mother and her john are beaten to death while they are asleep in bed, teen-aged Ellie Masters is sent to an isolated orphanage run by a mysterious woman and her handyman, both whom she comes to suspect are hiding dark secrets.
The inhabitants of a small, remote island have been practicing voodoo rites and worshipping an evil priest named Damballah for years, but the local law officials generally turn a blind eye to this death cult's bizarre activities. Captain Labesch arrives from the mainland, determined to crack down on the island's lawlessness and clean up the ineffectual, hard-drinking police force. He appeals for assistance from wealthy plantation tycoon Carl Van Molder, who owns nearly half of the island and wields a great deal of influence over the population. Van Molder has made the study of parapsychology his life's work and believes in the secret powers of the mind. He warns Labesch not to interfere with this forgotten island's ancient ways. Also visiting is Van Molder's niece, Annabella, a temperance crusader who wants her uncle to help fund the International Anti-Saloon League. She falls in love with handsome police lieutenant Andrew Wilhelm
After a schoolgirl is raped while taking a short cut through the local woods, and another murdered a few days later, the police are baffled. With the help of a reporter, and against the wishes of a local psychologist, a young schoolteacher uses herself as bait to lure the perpetrator out.
After a landsman in 18th century England discovers a corpse covered in fur buried in a field, the town becomes infected by "the devil's skin," leading the local children to engage in demonic rituals and criminal behavior.
When socialite and heiress Julie Wardh begins receiving blackmail letters attributed to a mysterious serial killer, she suspects her cruel and sadistic former lover Jean is behind them. With her husband Neil frequently out of town, she falls into the arms of her friend's cousin George, and as the unknown assassin begins to make his move, she fears that one of the three men in her life may be the killer.
In the heart of Styria the Karnstein Family, even after their mortal deaths, rise from their tombs spreading evil in the countryside in their lust for fresh blood. Baron Hartog whose family are all victims of Karnstein vampirism, opens their graves and drives a stake through their diabolical hearts. One grave he cannot locate is that of the legendary beautiful Mircalla Karnstein. Years of peace follow that grisly night until Mircalla reappears to avenge her family's decimation and satisfy her desire for blood.
A family of vampires takes over an estate known as Carfax Abbey. Since inbreeding is destroying the family line, they need new blood to keep the family going, so they set out to find new sources.
Two young English women go on a cycling tour of the French countryside. When one of them goes missing, the other begins to search for her. But who can she trust?
In seventeenth century England Lord Whitman wages unending war on what he sees as the ever-present scourge of witchcraft, and many local villagers have suffered at his hands. But one victim uses her occult powers to curse his family, enlisting unknowing help from one of the household.