This book picks up about four months after the first. If I recall correctly, I think it takes a bit for things to pick up as Allison reminds us of the importance of her current mission: Save Kanin, her vampire sire. She also muses for a bit about the fact that she left her dubious human love, Zeke Crosse, back at the human settlement known as Eden. As she goes, she closes in on the vampire holding her creator captive, a bat crazy vamp (pun intended) known as Sarren, who is apparently so powerful even Master vampires are wary of him. 
 Allison's search brings her to the remains of D.C. where she suspects (without knowing the significance of her surroundings) that Sarren is being held in the White House. But when she manages to get there, she finds instead her blood brother, Jackal, the former raider king and antagonist of the first book. Naturally she isn't happy about this, but Jackal explains that he had called Allison to him on purpose (using a sort of psychic blood link she had been using to track Kanin) because he wants her help to investigate a lab underground. She refuses at first until he persuades her by reminding her of just how dangerous Sarren is. Since he's going after the psychotic vampire too, they should work together, he reasons. Reluctantly, Allison agrees. 
 And that's how things start, essentially. Eventually we see some familiar faces, including the dreamy Zeke Crosse. (That isn't really a huge surprise, but I'll refrain on saying how he makes his return anyway.) The stakes are raised in this book when a new mutation of the Red Lung virus that had wiped out millions is released, thus threatening to wipe out what's left of the world's population. What at first was a race to save Kanin becomes so much more, and it's such a riveting read. 
 In the first book, the major question of the story seemed to be, "How can Allison maintain her humanity when she has become a monster?" That question still hums through The Eternity Cure, but it takes a back seat to the new theme: Loss. More specifically, coming to terms with it. Allison finds herself fighting to save two of the most important people in her new undead life, but she stands to lose them both in a tragic fashion that threatens to completely demolish her spirit. Can she let them go without losing what little grip she still maintains on her hope, sanity, and humanity? 
 Since Allison finds herself in the company of a number of vampires in this book, we get to see more of what vampires are like. I remarked in my review for The Immortal Rules how Kagawa's vampires, while very much traditional in style, are very satisfying. They are violent and ruthless. They remind me a lot of Anne Rice's idea of vampires, though I've never read any of Rice's books (only seen the movies). Some might not be too impressed by that, but given the saturation of vampires in the reading world today, I think Kagawa was smart to take the tried and true approach, and do it well. 
 In my reading updates on Goodreads, I talk about how Julie Kagawa manages an efficient and focused plot by wasting no time with unnecessary details. Just about everything, from her world building, to her scene setting, to even her character descriptions, serve a greater purpose. I admire a story with such a tight and focused narrative, and I take my hat off to Kagawa for her accomplishment. The Eternity Cure is certainly a bigger and better book than The Immortal Rules, but it it's bigger in the way of a massive tank--solid and powerful--and less like a giant squid--slippery and confusingly branching. 
 So do I recommend this installment of the Blood of Eden series? Yes! A thousand times, yes! It's got so much going for it, including a hot romance, a wise cracking vampire, and a fantastically evil antagonist. You really have no reason to skip out on this book if you liked The Immortal Rules. Even if you didn't like the first book somehow, the second book is an improvement of the first by leaps and bounds. 
 Bottom line: get this book. I don't give out five stars all that often, but this was certainly a five star book!