Mad Monster Party? is a 1967 stop-motion animated musical comedy film produced by Rankin/Bass Productions for Embassy Pictures. The film stars the voices of Boris Karloff, Allen Swift, Gale Garnett, and Phyllis Diller. It tells the story of a mad scientist who achieves the secret of total destruction as he summons all the monsters to his island home to show it off while planning to retire as the head of the "Worldwide Organization of Monsters".

Plot

On the Isle of Evil, Baron Boris von Frankenstein (voiced by Boris Karloff) achieves his ultimate ambition, the secret of total destruction. Having perfected and tested the formula, he sends out messenger bats to summon all monsters to the Isle of Evil in the Caribbean Sea. The Baron intends to inform them of his discovery and also to reveal his imminent retirement as head of the Worldwide Organization of Monsters.