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Secrets of the Phantom Caverns is a goofy fantasy filmed on the cheap by the ever-canny Don Sharp. The story involves a team of anthropologists and military men who busy themselves exploring a serpentine system of subterranean caves. They discover of lost race of Albinos, which wreaks havoc upon the surface dwelling humans. The British actor Robert Powell and Timothy Bottoms star. According to some sources, Sharp and co. approached the production with extreme carelessness; thanks to an unfortunate accident, a large percentage of the cast and crew were almost fatally poisoned by carbon monoxide in the caves where the movie was filmed.