Seventeen-year-old April Parker wakes up in an underground facility, a shock bracelet on her wrist and a five-day countdown on the clock. Dozens of other teens share her inexplicable fate, but their unseen captors never intervene no matter how brutal conditions become. When the ruthless - and unnervingly magnetic - Marcus seizes control, April's trauma-forged instinct is to lay low. But protecting her friends drives her to bargain with the boy she should fear most - a boy whose reality fractures with every tick. Then the countdown ends, and the real terror begins. Powers ignite. Alliances shatter. And predators are born. And with a saboteur among them determined to keep the doors closed forever, escaping what comes next may be the only way to survive it.

Mankind is evolving. Some love it, some fear it. Some embrace it, some envy it. For Zoey, the evolution of man has always been in the darkest part of her closet. A place no one touches. Only her family knew of her secret, and her stepfather never let the fact that Zoey was different disappear. But with mankind evolving, Zoey will soon figure out her own evolution is about to change more than she wants it too.