Overpopulation. 

It happened sooner than they expected. Society panicked and then came an idea. The rich, who would become known as the Elites, would survive, and create a new perfect society. While, the poor, the Inferior, would be hunted and killed. 

Melanie Sawyer thought she knew who she was until she is dragged into a war she didn't expect. And she soon learns that no one can be trusted...