Champion was written by Marie Lu in 2013 and was published by Putnam Juvenile. It is the third and final book of the Legend trilogy, which has received praise from Kirkus Review, The New York Times and USA Today, among other sources.
When asked about the trilogy's conclusion, Lu says that the ending is very different from the original one. She also explains that she wanted to explore issues of restructuring society following the collapse of a government, and what happens when a new ruler comes into power- and when outside forces come in to help. The series as a whole has focused closely on issues of power and government corruption, and how individual members of a society can unify to right that corruption.. It has also explored issues of class division and poverty.
Champion follows June and Day, a military prodigy and a thief from the slums, as they navigate the complex political world of the Republic, June as a government official, Day as a member of the military. As a plague sweeps the country and war looms on the horizon, the two are forced to protect their country while also protecting themselves and each other.