Obsidian Chamber (Agent Pendergast Series, 16)

A TRAGIC DISAPPEARANCE After a harrowing, otherworldly confrontation on the shores of Exmouth, Massachusetts, Special Agent A.X.L. Pendergast is missing, presumed dead. A SHOCKING RETURN Sick with grief, Pendergast's ward, Constance, retreats to her chambers beneath the family mansion at 891 Riverside Drive--only to be taken captive by a shadowy figure from the past. AN INTERNATIONAL MANHUNT Proctor, Pendergast's longtime bodyguard, springs to action, chasing Constance's kidnapper through cities, across oceans, and into wastelands unknown. BUT IN A WORLD OF BLACK AND WHITE, NOTHING IS AS IT SEEMS And by the time Proctor discovers the truth, a terrifying engine has stirred-and it may already be too late . . .