A group of present-day archeology students are stunned to discover a handwritten plea for help dated April 2, 1357...from their own professor. He's been blasted back in time to the 14th century. To rescue him, they must travel back and survive one of the most violent battles in world history--and make it back to the 21st century alive.

Desperate to alter the course of time, a visionary scientist invents a revolutionary machine that propels him 800,000 years into the future. There he discovers that humans have evolved into two groups: the hunters and the hunted. Now he must fight to save himself, and all of mankind, in a final, desperate battle.