Reliquary (Pendergast, #2)

Reliquary is the 1997 New York Times best-selling sequel to Relic, by American authors Douglas Preston and Lincoln Child. The legacy of the blood-maddened Mbwun lives on in Reliquary, but the focus is shifted from the original museum setting to the tunnels beneath the streets of New York City. The book is the second in the Special Agent Pendergast series.