After a narrow escape from the Tower, a twenty-six story apartment building, overrun with living dead, known as crits, and leading forty people to safety, Evan Stewart returns to the island in search of any last survivors. Concerned with the organized way the crits attacked the island, Evan approaches with caution and observes the crits. At first, they look to be doing what they always did, wander aimlessly in search of human flesh to devour, but as he watches, he begins to notice patterns in their behavior as if their actions have been thought out and planned. Were the crits evolving into thinking entities? If so, that made them more dangerous and deadly than ever and he fears for the survival of the human race.Sneaking on to the island, Evan finds survivors and works to get them safely away, until he discovers that the Island Defense Force, of which he is a Captain, has been feeding survivors to the crits to eliminate the human presence. Their ultimate goal is to take over the island for themselves. Once all humans are gone, they plan to systematically wipe out the invading crits. However, they greatly underestimate what the crits have become and an all out battle for survival ensues.Caught between the Force and the crits, Evan must find a way off the island leading a small group of men, women and children, before they are either gunned down or become food.