The film begins with a narration by Dr. Frank Baxter, an English professor at the University of Southern California, explaining the premise of the movie and its basis in reality. He briefly discusses the hollow earth theories of John Symmes and Cyrus Teed among others, and says that the movie is a fictionalized representation of this unorthodox point-of-view. In this movie, archaeologists Dr. Roger Bentley and Dr. Jud Bellamin stumble upon a race of Sumerian albinos living deep under the Earth. They keep mutant humanoid mole men as their slaves to harvest mushrooms, their primary food source, since they can grow without sunlight. The Sumerian albinos' ancestors moved into the subterranean after the cataclysmic floods in ancient Mesopotamia. Whenever their population increases, they sacrifice old people to the Eye of Ishtar, which is really natural light coming from the surface. These people have lived underground for so long that they are weakened by bright light which the archaeologists brought in the form of a flashlight. However, there is one girl who has natural Caucasian skin who is disdained by the others. They believe the men are messengers of Ishtar, their goddess. When one of the archaeologists is killed by a mole Person, Elinor, the High Priest realizes they are not gods. He orders their capture and takes the flashlight to control the Mole People, not knowing it is depleted. The archaeologists are then sent to the Eye just as the Mole People rebel. The girl goes to the Eye only to realize its true nature and the men had survived. They then leave for the surface. Unfortunately, the girl dies after reaching the surface, when an earthquake causes a column to fall over and crush her.