In a post-apocalyptic New York City obliterated by a Big Night that wiped out most of civilization, bands of children struggle to stay alive in the wreckage, hunting for food under billowing clouds of toxic fog and running from hungry zombies. One child is endowed with the power to keep them at bay, but will it be enough to protect the survivors from the terrifying creature that has just risen out of the Hudson River? Meanwhile, a raving old man with a house full of books says the worst is yet to come...

In a post-apocalyptic New York City where the toxic fog of the first Big Night turned most of the population into drooling zombies and drove pockets of survivors underground to hunt for food and live in hiding, a group of bickering teenagers and a raving old man set out to rescue a little boy from the clutches of the mysterious creatures that hold him and try to prevent the second Big Night from descending on the beleaguered city and destroying what's left of the sane human population.