This is a staple of its genre, and for good reason. It is hokey, it is overacted, the effects are messy, sure, but that does not makes it any less brilliant. While teasing some Lovecraft-story ideas, this is its own beast, and stands on its own legs. The casting is ok, apart from Jeffrey, of course, who is tearing up each and every scene. He is grand in this.
In 1985 I was 15, and already a big horror movie fan. With Evil Dead, Halloween, Friday 13th, Italian horror ... the genre was dynamic. Then, reading Mad Movies, I see this very gore movie inspired by a short Lovecraft tale, coming soon. I go there at 2pm, watch the movie and end up seeing it 7 times in 3 days. The cast gives an insane (!!!) performance, especially Jeffrey Combs of course, but...
