Here is the summary of the book:
Thor, the Norse god of thunder, is worse than a blowhard and a bully—he’s ruined countless lives and killed scores of innocents. After centuries, Viking vampire Leif Helgarson is ready to get his vengeance, and he’s asked his friend Atticus O’Sullivan, the last of the Druids, to help take down this Norse nightmare. One survival strategy has worked for Atticus for more than two thousand years: stay away from the guy with the lightning bolts. But things are heating up in Atticus’s home base of Tempe, Arizona. There’s a vampire turf war brewing, and Russian demon hunters who call themselves the Hammers of God are running rampant. Despite multiple warnings and portents of dire consequences, Atticus and Leif journey to the Norse plain of Asgard, where they team up with a werewolf, a sorcerer, and an army of frost giants for an epic showdown against vicious Valkyries, angry gods, and the hammer-wielding Thunder Thug himself.
Hammered picks up right after book 2 Hexed finishes. Our resident Iron druid is a man of his word. It is enough to understand that Atticus was born in the Iron age and so his oath keeping talent. And it was time he did something about them (even if they result in his getting in more trouble than before) even if they yielded life threatening results. Also in many ways this book is very different from the previous books Hounded and Hexed. In a way the title of the book is self-explanatory as to what is about to happen in here and if not the previous books provide some hints as to the happenings here.
Be it stealing a golden apple for a witch at a great cost to his life or following through with the promise he made to his vampire friend Leif (who coincidentally not a sparkly emo-vampire - THANK GOD!). Atticus is gain trifling with the fates. Hammered, practically gives us a rundown of the Norse myths brought to life by our faith. Faith does play a huge part in these don't you think - I mean come on even Spock and Captain Kirk have been realized by faith, among others, appearances by the vengeful Roman god of wine, an obscure Slavic thunder god, an immortal Chinese kung-fu master, and the most influential Christian figure of them all (who is for a lack of a better word - cool -- and even takes a swing at the sparkling emo-vampire).
Despite warning of world shattering consequences our resident Druid follows through with his plan to help his vampire attorney Leif Helgarson to bring an end to the thunder douche (don't mean any dis respect but i'm reviewing as they are put forth). Druid reality check - the Norse thunder God definitely deserves a serious smack-in-the-face. Several chapters are dedicated only to Thor's misdeeds against every member of the group as each share what Thor had done to them to deserve their hatred.
As with the previous books Hammered is filled with every inch of tantalizing action and every niche but there is a certain difference here, a slight change in the air. Things are much more different here, much more drastic and life changing than before. There's a sense of finality in how Atticus goes about putting his immediate plans into effect. And they go on a bumpy ride to where? None other than Asgard itself. Atticus may be as every bit a sarcastic fellow but he has one big quality he fulfills his oaths and at personal risk and conflicted mind he does the deed. Not only does this give a reality check to the Norse divinity but may also lay the foundation for the next chapter in Atticus' life.