A list of hiding places on a strip of papyrus found inside a mummy mask thrusts Graham Eliot, Ancient Near East scholar, into a hunt for the treasures of the second temple. The list has already cost the life of a colleague, and now he is being pursued as he races to recover what has been lost for almost 2,000 years.

As he literally digs into Jerusalem, he is haunted by the recent deaths of his wife and daughter, which have left him doubting the existence of God. His spiritual and archaeological struggles become more entwined as his life is repeatedly threatened the longer the work continues. When he reaches the final site—the cisterns below the Temple Mount, a network of caves and tunnel no one has entered in 150 years and that no one has ever explored—Graham discovers far greater treasure than he ever imagined.