Much like Abbott and Costello Meet Frankenstein and the upcoming Hotel Transylvania, this 1967 stop-motion animated movie from Rankin/Bass (Rudolph the Red-Nosed Reindeer) features a fun gathering of monsters. And legendary horror star Boris Karloff is even here to lend his voice to Baron von Frankenstein. The Baron decides to leave his monster business to his incompetent nephew, but the monsters decide to take over! Phyllis Diller, of all people, costars. Harvey Kurtzman of MAD Magazine cowrote the script.