Consumed by guilt from a war she started, Cori faces the aftermath of her destruction. The Mercy colony is in shambles as infection spreads and Dylan struggles to find a cure before it's too late. Cori's love and loyalties are put to the test when he asks her for the unthinkable. Now faced with impossible decisions, Cori must risk her friends and everything she's ever cared about in order to put things right. She'll go to unimaginable lengths to save the innocent, no matter the cost.