Sergeant Major Whitmore thought the nightmare was over. Three years following the incident on the island of South Fire, he enjoys the peaceful life of a retired man. But the past has a way of catching up to a man. When a mysterious and powerful figure reveals himself, Whitmore finds himself staring death in the eye once again. Caught in a web of lies and deceit, he is brought to an old naval research station in the eastern Pacific. There, he is forced to face his greatest adversary for the second time.

Its razor-sharp claws can sever limbs with minimal effort. Its mandibles can separate flesh from bone like tissue paper. The lance-shaped stinger on the end of its tail can penetrate two inches of steel. For its victims, death is a mercy. To those who created it, it is considered a scientific miracle. To everyone else, it is an unspeakable horror. To Whitmore, it is a Specimen of pure evil.

Replicated from the DNA of the creature on South Fire, it lives again. Sharing the intelligence and ruthlessness as its genetic forebear, it has outwitted the technology of Modern Man. Now it seeks to multiply its numbers by infecting any organism it comes across—terrestrial and marine. Only Whitmore and an unlikely band of allies stand in its way.