In the world of the future, humans uneasily walk side by side with "Kin"—humanoids with animal mutations. TASK was formed to help ease the way for human and Kin to exist together. The program also deals with the problems those differences cause.

Leander Kale and his partner, Epsilon Maddox, are one of TASK's top teams with a special bond all their own. Praised for their abilities and cursed for their existence, Leander and Epsilon struggle to do what they do best: hunt the Hunters, a breed of Kin that lives only to infect others and kill. But now there's a leak inside TASK, an informant telling the Hunters when a team is closing in, giving them a critical advantage and a chance to escape.

That leaves Leander, Epsilon, and the other TASK members fighting blind—fighting for their lives and the lives of all of humanity. All they need is one lead, one clue to help them find the traitor, and they have to find it before the Hunters invade TASK itself and destroy them all.