ENTOMBED WITH GOLD AND silver symbols of spiritual and temporal power, the Moche rulers of ancient Peru took their treasures, and their secrets, to the grave. Archaeologists studying extant murals, metalworks and ceramics could sketch an inexact portrait of the pre-Incan civilization that vanished around A.D. 800, but they were frustrated by the many remaining blank spaces. The absence of a written language meant there was no sure guide to lead them back to the lost culture.
Plunderers seeking gold were the first to find the shining key that would unlock a door to the past. In 1987 a local looter...