After being buried in quicksand for the past 25 years, Kharis is set free to roam the rural bayous of Louisiana, as is the soul of his beloved Princess Ananka, still housed in the body of Amina Mansouri, who seeks help and protection at a swamp draining project.
Deranged scientist, Gustav Niemann, escapes from prison and overtakes the director of a traveling chamber of horrors, soon reviving the infamous Count Dracula, the frozen Frankenstein Monster, and the Wolf Man.
An Egyptian high priest travels to America to reclaim the bodies of ancient Egyptian princess Ananka and her living guardian mummy Kharis. Learning that Ananka's spirit has been reincarnated into another body, he kidnaps a young woman of Egyptian descent with a mysterious resemblance to the princess. However, the high priest's greedy desires cause him to lose control of the mummy...
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 1918, an English family is terrorized by a vampire, until they learn how to deal with it. They think their troubles are over, but German bombs in WWII free the monster. He reclaims the soul of his wolfman ex-servant, and assuming the identity of a scientist who has just escaped from a concentration camp, he starts out on a plan to get revenge upon the family.
Carpathian Count Alucard is invited to the U.S. by a young heiress. Her boyfriend and local officials are suspicious of the newcomer, who is interested in the "virile" soil of the new world.
Following a tragic accident that leaves him disfigured, crazed composer Erique Claudin transformed into a masked phantom who schemes to make beautiful young soprano Christine Dubois the star of the opera and wreak revenge on those who stole his music.
Grave robbers open the grave of the wolf man and awaken him. He doesn't like the idea of being immortal and killing people when the moon is full so tries to find Dr. Frankenstein, in the hopes that the doctor can cure him. Dr. Frankenstein has died; however, his monster is found.
A Serbian émigré in Manhattan believes that, because of an ancient curse, any physical intimacy with the man she loves will turn her into a feline predator.
A high priest of Karnak travels to America with the living mummy Kharis (Lon Chaney Jr.) to kill all those who had desecrated the tomb of the Egyptian princess Ananka thirty years earlier.
Frankenstein's unscrupulous colleague, Dr. Bohmer, plans to transplant Ygor's brain so he can rule the world using the monster's body, but the plan goes sour when he turns malevolent and goes on a rampage.
After his brother's death, Larry Talbot returns home to his father and the family estate. Events soon take a turn for the worse when Larry is bitten by a werewolf.
Dr. Jekyll believes good and evil exist in everyone and creates a potion that allows his evil side, Mr. Hyde, to come to the fore. He faces horrible consequences when he lets his dark side run amok.
Kitty Carroll, an attractive store model, volunteers to become a test subject for a machine that will make her invisible so that she can use her invisibility to exact revenge on her ex-boss.
Dr. Paul Carruthers is frustrated because he thinks his employers, Mary Heath and Henry Morton, have cheated him out of the company's profits. He decides to get revenge by altering bats to grow twice their normal size and training them to attack when they smell a perfume of his own making. He mixes the perfume into a lotion, which he offers as a gift to Mary and Henry. When they turn up dead, a newspaper reporter decides to investigate.