Husband-and-wife team Sam and Remi Fargo are used to hunting for treasure, not people. But then a Texas oil baron contacts them with a personal plea: an investigator friend of the Fargos' was on a mission to find the oil baron's missing father-and now the investigator is missing, too. Would Sam and Remi be willing to look for them both? Though something about the situation doesn't quite add up, the Fargos agree to go on the search.

What they find will be beyond anything they could have imagined. On a journey that will take them to Tibet, Nepal, Bulgaria, India, and China, the Fargos will find themselves embroiled with black-market fossils, a centuries-old puzzle chest, the ancient Tibetan kingdom of Mustang, a balloon aircraft from a century before its time . . . and a skeleton that could turn the history of human evolution on its head.