4.5 stars! 
 I read this aloud to my twelve year-old son (who turned 13 just before we finished); he gives it 4 stars. 
 In the future, people work to make Mars habitable. Life is harsh and difficult for most, though the Golds are at the top of the hierarchy. The Reds are way down low. This class struggle, and a complex plot to take down the system, forms the core of Red Rising. 
 I loved getting to know Darrow, and the many other characters that interact with him. The characterizations are strong. I could tell how the brutality of their situation changed some of the characters. By the end, I certainly knew which way I wanted things to go. 
 The writing is polished and deep, and I liked it even more when I learned that it's Brown's first novel. It felt a bit like a more literary Hunger Games. So much happens over the various parts of the book, and it's quite long. In the end, it didn't matter. Brown pulls everything together masterfully, with just enough of a teaser of what's to come that I'm left twitching, but in a happy way. 
 Highly recommended!