Mare is a Red, a regular human girl who lives in a poverty-stricken town in a kingdom under the rule of the Silvers, non-human people with magical powers who bleed silver. When Mare discovers--very publicly--that she also has powers, powers that Reds aren't supposed to have, she is integrated into Silver society and swept up into intrigue, betrayal, and revolution. 
 For a book that's so heavily laden with YA dystopian tropes, this was actually a pretty good read. The foundational plot device was a bit shaky and hard to believe until the twist/reveal around three-quarters of the way through the book, but by then the explanation felt hand-wavy and wasn't quite enough to restore my suspension of disbelief. 
 I am deeply interested to learn how the Silvers got here and who they are, so I'll likely pick up the next in the series when it comes out. Worldbuilding is one thing Aveyard definitely has going for her in this book, and that kept me going even when the plot wasn't quite holding me.