The novel begins in the week before Halloween in the fictional western Maryland town of Stillwater in the days after a terrible flood has washed up the body of a hairless boy along the shores of the local culvert known as the Narrows.
Meanwhile, Maggie Quedentock is returning home late from an affair with her husband's friend when she strikes a pale, childlike creature with her car.
In the morning, Matthew's teenage sister Brandy awakes to find him missing and the back door of the house standing open.
Ben takes up the search for the Crawly boy, while simultaneously learning of instances of cattle mutilation that have occurred on local farms, where the animals appear partially digested by something akin to acid.
He learns from the local coroner that the body of the hairless boy who had washed up in the Narrows after the flood has mysteriously disappeared from the morgue.
Meanwhile, Brandy hears a noise outside at night, and when she goes to see about it, she catches a glimpse of the pale, vampire-like creature Matthew had become, before he vanishes through the cornfield.
A second boy, Billy Leary, disappears under similar circumstances, while other people in Stillwater claim to have seen visages of their dead loved ones while others are attacked by pale, childlike creatures in the night.
They had previously caught a bat, which they kept in a birdcage, and Ben straps a small vehicle tracker to it and sets it free, hoping it will lead him to the roost.
The pale, childlike creatures and being fed off the mother-creature by the mother's segmented tail, which inserts into a column of punctures along the spines of the boys.
In the epilogue, Brandy returns to the plastics factory to find her brother and the Leary boy turning back into normal children, while Ben leaves town, following the portable tracker, in search of the next bat infestation.
The book received generally favorable reviews, with Publishers Weekly calling it a "smartly written novel [that] succeeds as both an allegory of smalltown life and a tale of visceral horror.