** spoiler alert ** 
 I think the big question for this book is probably "why?" One version: Why did the author "switch" the direction of racist oppression between Blacks and Whites? Another version: Why, in our society, was that move necessary? I think the question of "why" could be discussed at length, but it has little to do with why I disliked this book. 
 First, some positives: It was well-paced and exciting, and full of twists and turns. It dissected a lot of the ways that oppression and racism work. 
 But the reason I was struggling to get through most of the latter part of the book is that it seems very intent on justifying rape. What? Yes. Callum raped Sephy, and that's not okay. And it kind of makes the whole resolution of the book not okay. Callum helped his cell kidnap Sephy, and then he had sex with her while she was his prisoner. I don't honestly care how Sephy felt about it: that's rape. From that scene to the end of the book I just kept hearing Sephy and Callum both try to argue that it wasn't rape, and I couldn't stop cringing. 
 That being said, there may be something deeper going on here. I think that one of the major ideas to take away from this book is how regardless of the direction of racial oppression, women and girls still somehow end up subjugated. It's evident from an early scene: when the Cross teacher talks about a bunch of Cross scientists and one girl in the room points out that they're all men, he brushes her off and continues the conversation he was trying to have about race. It sets the stage for a lot of the stuff Sephy has to go through - Callum kidnapping her in order to get to her father, her father nearly forcing her to get an abortion because he can't stand that she was knocked up by a nought, Callum's occasional violence toward Sephy and other Cross women that seems "justified" because Crosses are in power. It goes on and on. 
 Because the book ends with Sephy loudly declaring her love for Callum, I have to draw comparisons here with Romeo & Juliet. I think this book is about a lot of deep, dark, tragic stuff about the idiocy and violence of young love (because Sephy & Callum do A LOT of terrible things to each other), but I worry that teenagers will read it and never get past Callum & Sephy as perfect star-crossed lovers.