The Obsidian Chamber (Pendergast Series #16)

After Pendergast is presumed dead from a supernatural encounter, his bodyguard Proctor is the only one who can chase a kidnapper across international waters and into the deadly unknown.

A TRAGIC DISAPPEARANCE
After a harrowing, otherworldly confrontation on the shores of Exmouth, Massachussetts, 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--on...