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 being resurrected by grave robbers, Larry Talbot searches for Dr. Frankenstein in the hopes of being cured of his lycanthropy. The mad scientist may turn out to be dead, but his monster is just waiting to be found…

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.

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.

Victor Frankenstein witnesses his creation turn uncontrollable after he's duped by his associate, Dr. Polidori.