A war for Immunity has been waged

A formula has been created. One that will ensure immunity for all. But it's been stolen as a hidden enemy undermines every step to save the Vulnerables. Echo is doing everything she can to hunt the saboteur. River is about to discover he's more connected to this than he ever thought possible.

As they both learn they can't escape their roots, the people of the Dead Zone make it clear they're no longer willing to be cast aside. Immunity should be granted to all, not just the selected few. An uprising is inevitable. And the wealthy inhabitants of the Green Zone are determined to end it before it begins.

Echo and River will have to choose between love and loyalty. Because the race to find the formula has begun. And the fate of humanity depends on their success.