Once again, park ranger Jack Chastain is on a quest for answers. In 1765, Capitan Juan Rivera and a company of men left Santa Fe with orders to find a route into what is now Colorado, to look for gold and silver. He made two trips, found a little silver, and was largely forgotten by history. Over 250 years later, a leather-bound journal is discovered. It claims Rivera wasn't so much forgotten as he had chosen to disappear. He had plans-plans disrupted by a Comanche raid, but not before Rivera hid gold near present day Piedras Coloradas National Park. In Mexico, a butterfly biologist is murdered. That same night, an archeologist is killed near the park.

Nothing suggests the murders-hundreds of miles apart-are connected. They are.