|Publication date||July 5, 2011|
|Published by||Del Rey Books|
| Preceded by|
| Followed by|
Atticus O'Sullivan, last of the Druids, has lived for over 2,100 years, mostly by avoiding trouble. Though it appears that recently trouble has found him frequently. After dispatching a Celtic God fixated on vengeance, and preventing warring witch covens from devastating his hometown of Tempe, Arizona, Atticus hoped that he could focus on training his new initiate, the first in centuries. Instead, an old promise made to a friend leads him to band together with a werewolf, a vampire, an ancient Slavic thunder god, a Chinese Immortal, and a Finnish deity on a frantic mission to the land of Asgard. Their goal - to kill Thor.
- Atticus O'Sullivan: The last of the Druids.
- Oberon: Atticus' Irish Wolfhound; he can communicate telepathically with Atticus.
- The Morrigan: Celtic Chooser of the Slain and goddess of war.
- Malina Sokolowski: Witch of the Tempe Coven, guardian of Emily.
- Hallbjörn “Hal” Hauk: Atticus’ daytime lawyer who is also a werewolf.
- Leif Helgarson: Atticus' nighttime lawyer who is also a vampire.
- Widow MacDonagh: Atticus’ neighbor and friend.
- Granuaile: Bartender at Rúla Búla who is possessed by an Indian witch.
- Laksha Kulasekaran: Indian witch that possesses the bodies of others.
- Gunnar Magnusson: Lawyer, and leader of the Tempe pack who is also a werewolf.
- Perun: Slavic God of Thunder.
- Väinämöinen: Shamanic hero of the ancient culture of Finns.
- Zhang Guo Lao: One of China's Eight Immortals.
- Thor: Norse God of Thunder.
- Odin: The All-father, father of Thor.
- Jesus: Savior of Christianity.