A young heiress finds evidence suggesting that at night she acts under the influence of a family curse and has begun committing ghastly murders in a nearby park.
A scientist working on cures for rare afflictions, such as a bone softening agent made from molds to allow him to correct the spinal deformity of his nurse, finds the physical causes of lycanthropy in wolf-man Larry Talbot and of vampirism in Count Dracula, but himself becomes afflicted with homicidal madness while exchanging blood with Dracula.
On a Greek island during the 1912 war, several people are trapped by quarantine for the plague. If that isn't enough worry, one of the people—a superstitious old peasant—suspects a young woman of being a vampiric demon.
Edinburgh, 1831. Among those who undertake the illegal trade of grave robbery is Gray, ostensibly a cab driver. Formerly a medical student convicted of grave robbery, Gray holds a grudge against Dr. MacFarlane who had escaped detection and punishment.
Posing for a portrait, Dorian Gray talks with Lord Henry Wotton, who says that men should pursue their sensual longings, but laments that only the young get to do so. Taken with the idea, Dorian imagines a scenario in which the painting will age as he stays youthful. His wish comes true, and his boyish looks aid him as he indulges his every whim. But when a stunning revelation forces him to see what he's become, Dorian faces some very dangerous questions.
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...
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.