Right from the beginning, I was confused. Westerfeld dives right in, giving explanations for things after they have already happened. Then, as if I wasn't already confused enough, Cal explains that how Sarah was acting when he caught her wasn't normal (uh hello- you never told us what normal was!)
After things become a bit clearer I actually started to enjoy it. I have always had a certain respect for authors who take a such a common book theme, like vampires, and change it around completely. The first difference was the lack of a sappy love story. Yes I do love to read them, but the direction Peeps took romance was intriguing in a unique way. Because Cal is infected, he can't have a girlfriend. Worse than that, he can't even kiss a girl. That's right, if he does anything besides touch a girl they get infected. Talk about a twist.
The next difference I liked was the vampires, or peeps, themselves. In nearly every vampire book written, they are free to roam (though they usually spend most of their time out of the sun.) Even more, they are functional, and usually sane. In peeps, unless you have a rare case, like Cal's, the transformation leaves you schizophrenic, angry and anti-social to the extreme. They are in fact so different and creepy that they live mostly underground, with a brood of rats. I'm talking hundreds of them.
After taking in the differences between Peeps and most vampire books, I was bored again. Cal and Lacey's relationship never has any flame and only seems to become more and more boring with every page. When things start getting hectic, both Sarah and Morgan re-enter Cal's life and the book is once again confusing. On top of this, the build-up of meeting Morgan is completely pointless because the interaction between her and Cal is quick and unexciting. In fact, the only real contact they have is Cal running away from her house when she seems him and then him agreeing with her about spreading the disease. After a whole book of looking for her... that's it.
Unlike the Uglies series, Scott Westerfeld failed to impress me with this novel. The ups were mediocre and the down were boring, leaving me glad to be finished.