The Hunger Games Trilogy

 The Hunger Games, Catching Fire, and Mockingjay by Suzanne Collins, 1155 pages.

Every year two children are selected from the twelve poor and exploited districts that surround the luxurious capital of Panem. These 24 children are then sent into televised death matches where one winner will receive fame and fortune, and everyone else will just die. Katniss Everdeen volunteers, not because she thinks she will win, but to save her little sister from having to go. Acts of survival are interpreted as acts of rebellion until they become exactly that, and Katniss finds herself the figurehead of a long-overdue revolution. A revolution that may still cost her everything. 

I first read these books fifteen years ago, and I was a little surprised how remarkably well they still held up this much later. Suzanne Collins had a lot to say about systems of power and control, as well as plenty of other political issues, on a more complex level then you would expect from books written for teenagers, and especially books that are regularly marketed as a girl caught between two boys. Also, on a narrative level, these books are still emotionally devastating on a reread. I would definitely recommend them to anyone who passed them up because they're outside of their usual genre, or because they were unimpressed by the many imitators that came later.