I absolutely loved the book. Lauren Oliver's proven herself (in my eyes) as a fantastic writer with great ideas. In this book she managed to make me actually like the protagonist (and root for her) whereas in Before I Fall, it took much of the book before I was on Sam's side. 
 The idea behind the book is so intriguing to me, the way these people are brought up to believe that 'love' is such a bad thing. I loved watching Lena's gradual shift between fully supporting what the government has planned for her life to fully rebelling against it. 
 The only thing I did NOT like, and the reason this one didn't get five stars from me is because of that epic cliffhanger!! I understand authors wanting to sell more books, but that was just cruel. I loved the book, however, I now wish I would have waited for the second one before starting the series.