Catching Fire by Suzanne Collins

By winning the annual Hunger Games, District 12 tributes Katniss Everdeen and Peeta Mellark have secured a life of safety and plenty for themselves and their families, but because they won by defying the rules, they unwittingly become the faces of an impending rebellion.

Katniss Everdeen has won the annual Hunger Games with Peeta Mellark. But it had been a victory won by defiance of the Capitol and their harsh rules. Katniss and Peeta should be happy. But there are rumors of rebellion among the subjects, and Katniss and Peeta, to their horror, are the faces of that rebellion.