That would be a sinister, humming force that can turn people Witley's wife included into hideous mutant freaks. The special effects are not so special until you get a glimpse of the giant octopus or, better yet, when Witley turns into some sort of glowing metal man. (Again, don't ask why this is Lovecraft, after all.)
But the best special effect of all must be the see-through sweater of Suzan Farmer (Hammer's Dracula: Prince of Darkness), now visually crisper than ever thanks to Shout! Factory's Blu-ray release.
Five years after this, director Daniel Haller would tackle another Lovecraft adaptation, in 1970's superior The Dunwich Horror. As for Die, Monster, Die!, for the record, at no point does anyone shout the film's title. Rod Lott
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