Follows paleontologist John Flynn as he leads an international team of geologists and naturalists high into the Andes Mountains to unravel a mystery. In rocks thought to be 100 million years old, Flynn found the fossilized remains of small mammals only 32 million years old. The discovery raises questions about the area's entire geologic history, as well as the planet's. If Flynn and his team can find evidence to undermine old theories, it may open up a window to a new and better understanding of the earth.