Under siege…and out of control! The Armor Hunters have decimated a major metropolis, and the battle to save the survivors still rages. In the midst of the devastation, the volatile team of Harbinger Foundation escapees called Generation Zero are about to stumble headlong into an insidious alien counteroffensive — one with the potential to bring down not just a city, but the entire world. When push comes to shove, can this group of immensely powerful, immensely temperamental teenagers be trusted to repel the Armor Hunters' second wave? Absolutely not…but they're the only chance we've got!