This is a story that you will either love or hate. There is no in-between. I loved it, but I also hate that I loved it. Ok-deep breath, and let's get into this. 
 This story messed with my head. It made me realize how easily anyone could have access to someone's personal information, all courtesy of the internet. The main character, Joe, uses this to his advantage when he meets Beck and immediately wants to know more about her. However, it's not out of casual interest to see if she's on Facebook or not, it's obsessive. That's when this book got dark. 
 I'm just gonna put it out there- Joe is seriously twisted, and yet completely normal. I empathized with him. I found myself liking him for his blunt and funny thoughts, and then immediately he'd steal Beck's phone or spy on her through her window and I'd realize again that he's a sociopath. His thought process is terrifying, because I found that while it was insane, it made sense. I hated Beck. I never understood her reasoning for anything, but I also know that because it was from Joe's POV I didn't know what Beck was really like. The supporting characters were also each unique and well-written. They each held their own voice and were all a key element into making this story as great as it is. 
 This novel is written in second person, which I usually try to steer clear of, but I don't think this story could have been told any other way. It is also written in present tense, which is disconcerting at times because you're always privy to Joe's dark thoughts, and then it's like you're right there with him as he commits a bunch of messed up things. 
 This book was dark, yet I never felt overwhelmed. Caroline Kepnes has somehow managed to blend together so many different elements to create a story that cannot be defined as a certain type. It is definitely worth the read, and I HIGHLY recommend it. A brilliant, compelling novel, it has started yet another book hangover.