With the world fighting a losing battle against the multitudes of a fierce and unstoppable extraterrestrial invader, humankind is living on borrowed time. Amid chaos, and an impending Armageddon, the former Green Beret First Sergeant, biology teacher, and doting father-of-one Dan Forester, finds himself in the ruins of an alien-infested, peril-laden urban maze, struggling for survival and answers along with a doomed army of untried soldiers. Now, a handful of defenders carries the weight of the world's desperate hopes. Can they come by a second chance?