Tough-O-Meter

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Tree Line (5)

The good news? In a lot of ways, this book is super-easy to read. Yancey isn't interested in impressing us with a bunch of fancy metaphors and SAT dollar words, and the basics of what happens—aliens kill seven billion people—seem straightforward (and terrifying) enough.

The bad news? (Well, apart from the fact that seven billion people just died.) There are a couple of things that have the potential to trip you up. One is the frequent shifts between narrators. We swing back and forth between Cassie and Ben's points of view (with a couple others thrown in there for good measure), and all that jumping around can be disorienting.

The other thing to watch out for is that some alien identities (like Evan and Vosch) aren't a hundred percent spelled out until we're deep into the novel. Yancey's very generous with the clues, so we're pretty sure about who's who.

And if you're confused, hey, that's the point. Have faith—all doubts should be cleared up by the end of the book. Yancey wouldn't leave us hanging like that. (Well, apart from the big, fat cliffhanger of what happens to Evan, but that's a different story.)