Does the physical evidence found in ancient ruins support the existence of lost civilizations or extraterrestrial intervention, or are these theories merely modern myths? L. Sprague de Camp, a prolific writer with a keen interest in history and science, examines the archaeological record of twelve distinct ancient civilizations. He applies a skeptical, rationalist framework to evaluate popular fringe theories regarding Atlantis, ancient astronauts, and the origins of human technological advancement.

This work serves as a grounded, skeptical counterpoint to speculative literature regarding ancient history. The text provides a clear, accessible methodology for readers to distinguish between archaeological evidence and pseudoscientific conjecture.