The Voices of Boris Karloff, Phyllis Diller, and Ethel Ennis. Frankenstein celebrates his retirement by throwing a bash and inviting every ghoul in town in this animated feature using three-dimensional figures in a stop-motion process called 'Animagic'.

Aging Baron Boris von Frankenstein, who lives on a Caribbean island with his monster, his wife, and his ward, Francesca, discovers the secret of total destruction, thus completing research that began with the discovery of the secret of creation. He decides to hold a convention for the world's most renowned monsters so that he may choose a successor to lead the Worldwide Organization of Monsters and to inherit his secret. The guests include Dracula, The Werewolf, the Creature from the Black Lagoon, It, Yetch (a Peter Lorre characterization), The Invisible Man (as played by Claude Rains), Dr. Jekyll and Mr. Hyde, The Mummy, Quasimodo (as played by Charles Laughton), and King Kong. Felix Flanken, Frankenstein's supposedly normal nephew, kept in ignorance of the proceedings, falls in love with Francesca, unaware that she is one of his uncle's mechanical creations. Intrigue follows intrigue as the monsters try to surpass one another to gain the prestigious position. Francesca meets with a surprise when Felix's identity is revealed.