The brains of a Russian taxi driver and a wealthy businessman are brought together in one body by a mad scientist.

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…

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.

Aliens from a dying world plot to conquer earth by preying on man's superstitions. Bringing two dead scientists back to life, they use their knowledge to re-animate various earth monsters, including the werewolf, Frankenstein's monster, the mummy Tao-Tet, and the vampire Count de Meirhoff.

Young couple Scott and Mary are on their way to a Halloween party when their car breaks down, and they encounter a creepy castle where Dr. Frankenstein seeks to put Scott's brain in his monstrous creation. As for Mary, Count Dracula wants her for his mistress.