Connecticut middle-schooler Jake and his older sister Kady are transported by a Mayan artifact to a strange world inhabited by a mix of people from long-lost civilizations who are threatened by prehistoric creatures and an evil alchemist, the Skull King.

"In this groundbreaking masterpiece of ingenuity and intrigue that spans 50,000 years of human history, New York Times bestselling author James Rollins takes us to mankind's next great leap. But will it mark a new chapter in our development. or our extinction? A war is coming, a battle that will stretch from the prehistoric forests of the ancient past to the cutting-edge research labs of today. In the remote mountains of Croatia, an archaeologist...