I enjoyed this more than I thought, and more than I did the first book. Unfortunately, one of the main twists was ruined for me before the start of the book (even though I kind of saw it coming... at least part of it) so I feel the need to warn you that there will be spoilers below.
The book doesn't start off necessarily right where the first left off. The chapters switch between 'then' (which is right where we left off) and 'now' (which is in the near future). Most of you know how much I think that this tactic is overused and usually unnecessary. I didn't mind it here so much, but I don't think that it was completely needed. Anyways, we learn that Lena ran non-stop until she collapsed and was found half-dead. She woke up and built herself back up with new friends and thought of Alex all the time, even though she believed him to be dead.
Eventually (now), we learn that she's living under an alias in New York as part of the revolution and has orders to watch the son of the DFA's leader (Deliria Free America). She hates him for being exactly the way she used to be blablabla and of course ends up falling in love with him, because what else would possibly happen?
The end reveals that Alex was actually alive in the crypts and broke free so of course now there's a love triangle, because that's what every YA book needs, apparently. This was the part that was ruined for me, although I could have guessed he was alive. I don't know why people don't hide major spoilers like that... even though it isn't probable that the author would kill off a main character/love interest (especially when they can make a triangle!!!). But, I did like that Lena didn't INSTANTLY fall for Julian, it happened over time (even though it was actually a few days) and she felt guilty because it's not what she wanted. She was still grieving for Alex, after all. I am proud of Lena for toughening up and refusing to sacrifice anyone, even if it's for a good cause.
The whole mother thing was really obvious, but it seemed like an afterthought. Of course we knew that her mother was still alive, but they just kind of threw her in there. I hope she has some sort of use in the next book.
Overall, the book was okay. It wasn't something completely original but it was a safe extension of the first book. I'm hoping the next one has some wild ending to throw me off, but I'm guessing if other people liked it that isn't the case. We'll have to see.