A narration by Dr. Frank Baxter, an English professor at the University of Southern California, frames the story and its relation to reality. He briefly surveys the Hollow Earth theories of John Symmes and Cyrus Teed, noting that the film presents a fictionalized representation of these unorthodox ideas.
Archaeologists Dr. Roger Bentley and Dr. Jud Bellamin venture into an unseen world and uncover a hidden race of Sumerian albinos living deep beneath the Earth. These people keep mutant humanoid mole men as slaves to harvest mushrooms, which serve as their primary food source. The survivors trace their roots to ancestors who retreated underground after cataclysmic floods in ancient Mesopotamia, building a secret civilization far from the sun.
The subterranean society believes the men are messengers of Ishtar, their goddess, and their rituals reflect that reverence. As their population grows, they sanction sacrifices of young women to the enigmatic Eye of Ishtar, a practice born of myth and necessity, or so they believe. In this world, the inhabitants have spent so long in darkness that the arrival of the archaeologists’ flashlight unsettles them, making even the light feel alien.
Among the underground community there is Adad, a girl with natural white skin who stands out and is shunned for bearing the so‑called “mark of darkness.” When disaster strikes and one archaeologist is killed by a mole person, Elinu, the High Priest, concludes that the foreign visitors are not divine beings at all. He seizes the flashlight and uses its light to try to control the Mole People, unaware that its power is already waning.
Against this backdrop, the two scientists are captured and sent toward the Eye of Ishtar as the Mole People begin to rebel. Adad dares to approach the Eye, hoping for insight, only to discover that the Eye’s reality is simpler than the myth: it is nothing more than natural daylight seeping down from the surface, confirming that the surface world—and its people—have endured. With the truth revealed, they begin a perilous ascent toward the world above, climbing toward freedom. Yet as they near the exit, an earthquake shatters the underground calm, and in the final, tragic turn, Adad chooses to return home, where a falling pillar claims her life.
In this tale of discovery and danger, the boundaries between belief and truth blur, and the explorers face the consequences of intruding on a society that has learned to survive in the dim and the dark. The narrative balances wonder with caution, inviting readers to weigh the allure of ancient myths against the stubborn resilience of humanity.
