Explorers of the New Century : At the dawn of a great age of exploration - closely resembling that of Shackleton and Perry and Scott - two teams of explorers set off through an arid, lifeless landscape. Both are vying to reach the Agreed Furthest Point, or AFP, first: One team takes the western route across seemingly endless rocky scree; the other negotiates a dry riverbed. And both rely heavily on their mules for survival. The burden of that dependency bears a price. The white-knuckle drama of the race to reach the AFP pales in comparison to the revelation Magnus Mills delivers in this riveting tour de force, a revelation that changes just about everything.