When young paleontologist, Ryan Thompson, finds a new species of mosasaur in Cretaceous seaway sediments, he is thrilled. Joy quickly turns to fear when he touches an artifact buried among the sea reptile's ribs. Suddenly, he must fight a mental takeover by an alien intelligence committed to transforming the Earth into a refuge for her own species. As Ryan and his girlfriend, Skeets, attempt to thwart alien plans to colonize Earth begun in the deep past, even this crisis becomes trivial when the uneasy symbiosis of Ryan and the alien, Siu, generates a new entity with the power to transform...