***Note: this review presumes that you've read the book.***
I picked this up eagerly because I loved THE MONSTRUMOLOGIST, and I wanted to read more of Yancey's writing. I'm not as impressed with this effort, which seems to be an attempt to go more "mainstream YA," and sacrifices the...thoughtfulness and intellect, I guess I'd say. As a fun action read, it succeeds well enough, but it's not the literary work I was hoping for.
The good. The relationship between Cassie and her little brother, Sam, was great. Cassie's initial strength is well tempered with her own occasional lack of faith in herself. The idea that aliens are gradually destroying the human race in waves (in order to preserve the planet for themselves) is cool for the psychological terror it creates in the survivors. In fact, the themes of trust and what it means to be human are excellent.
Plausibility is the killer flaw. It started to nag at me when we began to learn that the aliens have been watching humans for years, and it solidified when we heard that their observations of us started a full 6,000 years ago (4,000 B.C.E.). At that time on earth, there were only something like 7-14 million human beings alive, with primitive technology. Why would a couple of hundred thousand aliens sit around for 6,000 years "studying," watching a species grow to 9 billion with advanced technology? What other alternatives could they have come up with in 6,000 years? How about sterilizing the population and letting the species die out? How about carrying out the same plan, but earlier--infest humans, "invent" more advanced weaponry, and then exterminate?
Sloppy YA tropes. I'm not sure whether Yancey has included romance in his other books, but the love affair between Cassie (formerly a quite strong character, who becomes somewhat stupid around Evan) and Evan was all shorthand. His breath smells of chocolate, his hands are like clouds, he has a lopsided smile, he wants to protect her. If you've read a lot of YA, you've seen these substitutes-for-relationship before. Evan is a creepy stalker a la Edward Cullen for a while, which does actually keep us nicely on edge about his personality (did Yancey mean that?), but he seems to redeem himself completely (no more gray area!) by the end.
Sloppy plot points. We've had four waves, billions of people have been killed, and there are still cases of bottled water in random 7-Elevens? I think not. How did Evan know what Cassie was thinking in the woods just before he shot her? She hadn't written it down in her diary by that time. Why create an army using kids? (Will this be explained further in the next installment, perhaps?) Why do the kids not question more vocally that this government that claims to want to protect them is grooming them to be soldiers? And related to that question is the observation that the switch to "vengeful soldier" that we see in Ben right before deployment happens too suddenly. Another detail that made me stumble (but maybe I misunderstood something): Vosch admits to killing human refugees older than 15, and Cassie is turned away from the bus at 16 (even though there are two free seats), but Ben was taken in as a recruit at whatever similar age he is (17?). What gives? I know we need Cassie to be on the "outside" to advance the action, but the alien plan should be consistent.
Derivative. There were moments when I thought, "This is from Doctor Who" (the aliens moving their intellects into machines, like Daleks); "This is like Walking Dead and The Road" (scrounging supplies from grocery stores); "This is like Fullmetal Jacket" (the recruits speech in boot camp); "This is like The Hunger Games" (kids younger than teens being trained to be experts in killing with adult weaponry*).
Unlike other readers, I didn't think Yancey was moving toward a love triangle at the end (we see our little band reunited, all except Evan, and Cassie and Ben have a quiet moment reacquainting themselves since high school). It seemed more that Yancey didn't want us to think that Cassie's high school emotional life was irrelevant, despite an apocalyptic change in the world. It's part of the theme of humanity--what makes us human--in the book. In the end Cassie simply pauses to remember the crush, from her changed point of view and circumstance. And as we all would, she remembers it with a kind of lingering sentimental "tingle," even while recognizing Ben's bond with Ringer and her own strong feelings for Evan (which I think solidified when he followed her into the camp--she truly came to trust him).
*Perhaps Ringer is going to turn out to be Other in the sequel, precisely because she's too good of a shot, she talks about chess, and she advises Ben/Zombie to "become one with the target" just as Evan did. If this doesn't turn out to be true, these similarities will feel like another sort of sloppiness on Yancey's part for me.