Skyhunter #1 by Marie Lu

My name is Talin, and most of the other Strikers doubted that a refugee like me belonged with this elite fighting force, especially when I was forced to kill my partner, my Shield. Injuries from a Federation attack when I was a child have left me unable to speak, and that only adds to my feeling of isolation. Later, I sensed a prisoner wanted to die while being questioned, and I dared to challenge our Firstblade in front of all the Strikers. As punishment, he embarrassed me by making the prisoner, Red, my new Shield! However, Red and I have mentally bonded and can communicate with our minds, and I've discovered secrets about him. This boy may be Mara's greatest weapon, but he could just as easily destroy us all. 

The audience for this book is a bit older than middle grade, although young teens can enjoy it. Kale and Red's relationship will clearly mature as the series moves along. Violence is a big part of the plot, as Talin's whole life is focused on protecting the country of Mara from the Ghosts and a Federation invasion. Ghosts are mutated humans and can only be killed by slitting their throats. This leads to some gross and bloody moments. Despite her heroic efforts, Talin's situation brings up the question of patriotism among immigrants. Can immigrants be as loyal as the country's natives? Why would an immigrant want to protect a country that doesn't treat her people as equals? As with most plots involving politics, this book has its share of conspiracies and power plays. Characters need to be cautious about who they befriend and who they offend. The Federation is a juggernaut that seemingly can't be stopped by the small forces guarding Mara, and the plot later reveals that there's something more important about this doomed city. Overall, the story is interesting, albeit violent, and the sequel should be even more compelling. The resolution reveals a series-changing decision made by Kale.