This is definitely going to have rate with one of the greatest Jeffery Combs movies ever. It is an unusual sci-fi spoof. Basically the heroes of our story are going down to the centre of the Earth after a secret stash of diamonds. Once inside they meet: mutant cannibals, killer robots, underground Amazon women, sex crazed Alien Queens (Sybil Danning from Amazon Women of the Moon), dinosaurs, and a host of other weird characters. I had a hard time finding this movie, but it was definitely worth the search.