The FBI's Clarence Otto and CIA agent Dew Phillips comb the country, ruthlessly eliminating people whose minds have been taken over by the mysterious disease sweeping America.

The black-ops team is proving a formidable weapon, thanks to the third member of their cadre: one-time football hero Perry Dawsey, once a victim of the disease, now a bloodthirsty psychotic possessed with a strange, valuable new ability.

But the enemy is learning, adapting, and has created a new breed of infected, sending nests of enslaved humans spreading through the American population. And this new generation is contagious.

Government biologist Margaret Montoya must now help Perry, Dew, and Otto stop this new assault, before the only containment option becomes a nuclear strike on major US cities.