In Ilmarsh, England, local police detective Alec Nichols discovers sixteen horses' heads on a farm, each buried with a single eye facing the low winter sun. After Veterinary Forensics expert Cooper Allen travels to the scene, a pathogen is discovered lurking within the soil, and many of those who have come into contact with the corpses grow critically ill.
A series of crimes comes to light—disappearances, arson, and mutilations—and in the dark days that follow, the town slips into panic and paranoia. Everything is not as it seems. Anyone could be a suspect. And as Cooper finds herself unable to leave town, Alec is stalked by an unseen threat. The two investigators race to uncover the truth behind these frightened and insidious mysteries—no matter the cost.