Cyrus and Antigone Smith haven't stopped running since they faced Dr. Phoenix in a burning cigar factory on the Mississippi River. They survived that clash, but their enemies—the enemies of mankind—grow stronger. Radu Bey builds himself a horrific temple in Manhattan, where he gathers his transmortal army and thousands of worshippers. Phoenix prepares his new race for their first assault on Ashtown and the world. Cyrus and Antigone would love to hide somewhere quiet, but if they don't stand and fight, who will? With the help of their small band of friends, a crazy Irish monk with a Mohawk, a solemn orangutan, and two of the deepest and deadliest secrets in all of Ashtown, they prepare to lose everything so that the world might not.
It's been almost a year since Cyrus and Antigone Smith earned their places as Journeymen at Ashtown, home of an ancient order of explorers that has long guarded the world's secrets and treasures. While their studies go well, Cy and Tigs are not well liked since losing the Dragon's Tooth to the nefarious Dr. Phoenix. The Tooth is the only object in the world capable of killing the long-lived transmortals, and Phoenix has been tracking them down one-by-one, and murdering them.
The surviving transmortals, led by legendary warrior Gilgamesh of Uruk, descend on Ashtown in force, demanding justice. Cy and Tigs find themselves on the run in a desperate search to locate Phoenix and regain the Tooth. In the process, they uncover an evil even more dangerous than Phoenix, one that has been waiting for centuries to emerge.
For two years, Cyrus and Antigone Smith have run a sagging roadside motel with their older brother, Daniel. Nothing ever seems to happen. Then a strange old man with bone tattoos arrives, demanding a specific room.
Less than 24 hours later, the old man is dead. The motel has burned, and Daniel is missing. And Cyrus and Antigone are kneeling in a crowded hall, swearing an oath to an order of explorers who have long served as caretakers of the world's secrets, keepers of powerful relics from lost civilizations, and jailers to unkillable criminals who have terrorized the world for millennia.