I really enjoyed books 1&2, but this was hard to stomach. I get that Atticus needed to fulfill his promise and go to Asgard to get some magic apples - I get that. But I didn't expect to actually see it happen. This book could have been summed up in one paragraph, so that the reader could have gotten back with the happy-go-lucky 2100 year old Druid.
Instead he decides to write a detailed account of Atticus with Asgard while leaving the characters we love behind on earth, leaving us to labor through ridiculous imaginary conversations amongst Cpt. Kirk, Spock, and Attitcus. And yeah, I'm not a Trekkie, but I do have some Trek-sense. Spock would not be much into cursing. "It's just not logical."
Anyway, this book was exactly what I expected would happen: that Hearne would jump the shark. So now I feel like Padme: "Hearne, you're taking me to place that I cannot go" - a ridiculous line for a ridiculous book.