Sherlock Holmes and Dr. Watson look into reports that a huge, vicious hound has killed Lord Charles Baskerville and that Lord Henry Baskerville is the next to be killed.
Dr. Frankenstein and his monster both turn out to be alive, not killed as previously believed. Dr. Frankenstein wants to get out of the evil experiment business, but when a mad scientist, Dr. Pretorius, kidnaps his wife, Dr. Frankenstein agrees to help him create a new creature.
When old-school monsters Frank, Drac and Wolf are deemed "fun" by a court of elders, they're ordered to scare a suburban family or risk a sentence of party entertainers for eternity.
Baggage handlers Bud and Lou accidentally stumble upon Frankenstein's Monster, Dracula and the Wolf Man.
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.
Blackmailing a young couple to assist with his horrific experiments the Baron, desperate for vital medical data, abducts a man from an insane asylum. On route the abductee dies and the Baron and his assistant transplant his brain into a corpse. The creature is tormented by a trapped soul in an alien shell and, after a visit to his wife who violently rejects his monstrous form, the creature wreaks his revenge on the perpetrator of his misery: Baron Frankenstein.
One of the sons of late Dr. Henry Frankenstein finds his father's ghoulish creation in a coma and revives him, only to find out the monster is controlled by Ygor who is bent on revenge.
Baron Victor Frankenstein has discovered life's secret and unleashed a blood-curdling chain of events resulting from his creation: a cursed creature with a horrid face — and a tendency to kill.
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.
A deformed tormented girl drowns herself after her lover is framed for murder and guillotined. Baron Frankenstein, experimenting with the transfer of souls, places the boy's soul into her body, bringing Christina back to life. Driven by revenge, she carries out a violent retribution on those responsible for both deaths.
Dr Simon Helder, sentenced to an insane asylum for crimes against humanity, recognises its director as the brilliant Baron Frankenstein, the man whose work he had been trying to emulate before his imprisonment. Frankenstein utilises Helder's medical knowledge for a project he has been working on for some time. He is assembling a man from vital organs extracted from various inmates in the asylum. And the Baron will resort to murder to acquire the perfect specimens for his most ambitious project ever.