This book is all about the questioning. It's a sci-fi novel about an alien invasion. It's all about these aliens who are trying to wipe out humanity, to then take Earth for themselves. They do this through different stages called 'waves'. The first wave was an electro-magnetic pulse that shut down everything. TV, computer, cars, none of it worked anymore. Then throughout the next 3 waves, 97% of the world's population is decimated.
This novel is mainly centered around 17yr old kick-ass Cassie short for Cassiopeia who survived the first 3/4 waves and is still surviving. This novel is told from various POV's and then all these different perspectives mold together perfectly to create a well-written and executed novel that keeps you on your toes wondering if what you know is right or not.
Throughout this entire book, all these hints are dropped about the plot twist and you notice them, you second-guess it. You keep on thinking "There's something more to this, this is too obvious." But Rick Yancey puts a sort of block on that second-guessing. You only second-guess to an extent before it kind of falls to the back of your head as another fact. The whole way through, you're filled with paranoia, alongside Cassie wondering "Who can we trust, who can't we trust? Who's human, who isn't?"
This goes perfectly with one of the major concepts of this novel which is 'trust'. Knowing who to trust and who not to, and sometimes you have no choice but to trust.
Overall, this book was fantastic! The writing style was a bit off-putting for me, so I don't feel like it deserves 5 stars. But it was REALLY REALLY good!! I definitely recommend you pick this up!