Ethan Wate used to think of Gatlin, the small Southern town he had always called home, as a place where nothing ever changed, not the people, the sights, or the traditions. Then he met mysterious newcomer Lena Duchannes, who revealed a secret world that had been hidden in plain sight all along. A Gatlin that harbored ancient secrets beneath its moss-covered oaks and cracked sidewalks. A Gatlin where a curse has marked Lena's family of powerful Supernaturals for generations. A Gatlin where impossible, magical, life-altering events happen, events that would change Ethan's life forever, or end it...

Together they can face anything Gatlin throws at them, but after suffering the tragic loss of Macon, Lena's cherished Uncle and succubus, Lena starts to pull away, keeping secrets that test their relationship. Now that Ethan's eyes have been opened to the darker side of Gatlin, there's no going back, he is the key whether he wants to be or not. Haunted by strange visions only he can see, Ethan is pulled deeper into his town's tangled history and finds himself caught up in the dangerous network of underground passageways endlessly crisscrossing the South, where nothing is as it seems. As he travels through the tunnels to find Lena, will he survive the dangers lurking inside?