For centuries, the existence of the Abominable Snowman, also known as the Yeti, has been a topic of speculation. However, a recent discovery in the Himalayas has brought this legend to life. A specimen has been found and sent to the United States for research, led by renowned anthropologist Doctor Claire Collier. The autopsy reveals that the creature underwent cranial surgery before its death, leaving many questions unanswered. To solve the mystery, an expedition is formed, consisting of Collier, her former student and writer Mat Connor, ex-big game hunter Rondo Montana, and guide Kathleen Reidel. The team's journey takes them through an avalanche and into an ice cavern, where they discover a hidden valley inhabited by prehistoric species. They soon find evidence of an intelligent lifeform, which leads them to a remote cave with a hydroelectric system and an abandoned space ship. However, their discovery is met with capture by reptilian-human hybrids, who have a deadly plan for the humans unless they can find a way out.

The Primevals
A long-forgotten civilization resurfaces from the depths of time, having remained dormant for over a million years.