What Waits Below

The U.S. military is conducting an experiment with a unique radio transmitter designed for submarine communication, situated within a network of deep underground caves in Central America. When one transmitter’s signal unexpectedly vanishes, a group of soldiers under Major Elbert Stevens (Bottoms) and cave experts led by Rupert ‘Wolf’ Wolfsen (Powell), along with scientist Leslie Peterson (Blount), are dispatched to investigate the situation. As they delve deeper into the caves, they encounter a tribe of albino cave inhabitants who have seemingly been cut off from the outside world for millennia. These cave-dwellers are sensitive to radio frequencies and possess the ability to perceive in infrared, allowing them to track the explorers by their body heat.