3.5-3.75 stars 
 I'm a little torn on it. One the one hand, it was really fast-paced, and it did keep my attention, but I think it's one of those where everything went by just a little too fast in some key places. 
 The setting: here is where I think that Lu did an awesome job. We are in Los Angeles, in the Republic of California. A military state at war with the Colonies and combating fighting within from the Patriots. There has been massive flooding on the coasts and throughout the US, I think there might still be aftereffects from volcanic activity, and in that chaos, the Republic was formed. It's a tyranny, of course, with experiments in weeding out "defective" genes, trying to create perfect soldiers.It's also treason to mention that there was once a "United" States. Lots of things here that can be explored (and I'm sure that there will be more books in this series). 
 The characters: the POV switches between the two main characters, Day & June. Day is a criminal wanted by the Republic of California. He recently discovered that his youngest brother has the plague, and he is desperate to steal the right medicine to give him. June is the shining star of the Republic's educational system - she received a perfect score on her Trials (a test 10 year olds take to decide where they will go in life). A wanted criminal has killed her brother and now she needs to catch him. I thought both characters were defined well enough so that I always knew which character was in the captain's chair. I also thought that each was a bit too perfect. Almost superhuman feats of physical prowess, beautiful people, although with the genetic manipulation, this wasn't too hard to believe, but I still was a bit put off. At least they did show vulnerability and they did get hurt on occasion. 
 The side characters: these weren't fleshed out as much as I would have liked. You got a feel for a couple of core ones, but since you already had 2 POVs propelling the story along, it was difficult to get a better feel for secondary characters. 
 The Romance: Here's the thing, I don't mind romance in books. I really don't. And I think if the romance happened later in the series, allowing things to progress a bit, I might be happier with it. There's a lot going on here: betrayals, lies, mortal danger, death of loved ones. There are many reasons for Day & June to be drawn together, and those are there, but sometimes the romance seemed to be more of a driving force, and I just wasn't feeling it. 
 I'll still read the next one, like I said, there is room for some interesting goings-on, and I do really like the world Lu created. I just have a few reservations.