It's the post-apocalypse, and the world has been changed by "the accident", a chemical warfare experiment gone awry. At an isolated subterranean complex, a group of people survived because they were able to get the antidote for the illness. They rescue a surface survivor from the gargoyles, who unfortunately had time to impregnate her, and when the "baby" is born and escapes into the ventilation ducts, they begin experiencing an attrition problem.—Ed Sutton
When chemical warfare leaves the world barren and filled with mutated monsters, a band of survivors in an underground complex battle one of the creatures that was able to break in.