Art restorer and sometime spy Gabriel Allon is sent to Vienna to discover the truth behind a bombing that killed an old friend, but while there he encounters something that turns his world upside down. It is a face -a face that feels hauntingly familiar, a face that chills him to the bone and sends him on an urgent hunt for more: a name, a history, a connection.
Each fact he uncovers, however, only leads to more questions: each layer he strips away reveals more layers beneath. Finally, a picture begins to emerge, but one more terrible than he could have imagined, a portrait of evil stretching across sixty years and thousands of lives and into his own personal nightmares. Soon the quest for one monster becomes the quest for many. And the monsters are stirring. . . .