Zombies have been done before, of course, but these feel much more terrifying. They have the speed of any other predator and are learning, like in Aftertime. What they reminded me of more than anything actually were the morlocks from The Time Machine. Super creepy! And they're not the only terror: "I had begun to throb with the desire to understand why things happened, why some people lived under the ground, like our enclave, the Freaks, and the Burrowers, and why some stayed Topside and turned into the greatest monsters of all" (173).
Speaking of figuring out why things happened, that is something I would still like to know. That explanation has yet to appear. Thankfully, this does not come across as a lame attempt to increase my interest, but as a part of Deuce's journey that has not yet come. Deuce feels so real. The comparison to The Hunger Games lies largely in Deuce. We see from her perspective and she, like Katniss, cares first and foremost about survival. She doesn't really want to be involved in politics and relationships definitely confuse her. I am digging her love triangle, but have not firmly declared support for either team (Fade vs. Stalker), as both have promise.
To sum up, I loved this and recommend it to pretty much everyone who likes reading darker stuff, like dystopias. This one rocks, especially because the characters go to a library to research in their post-catastrophe world. Now that's awesome! Ann Aguirre is officially on my watch list.