Nahum is a stolid, unimaginative farmer living near Arkham whose property becomes the crash site of a bizarre meteorite. He relies on his land to support his wife and three sons. When strange events begin occurring around his property, his passivity hinders his ability to respond or seek escape.

Ammi is a local farmer, somewhat better educated and more well-spoken than his rustic neighbors. He observes the strange phenomena occurring on the Gardner farm from a distance. He attempts to act as a voice of reason, advising his neighbor to take precautions like digging a new well.

The narrator is an inquisitive surveyor tasked with evaluating a valley slated to be flooded. He possesses a strong curiosity that drives him to investigate local legends about the blasted heath. He functions as an outside observer confronting an environment steeped in unidentifiable horror.

She is the matriarch of the Gardner family. She initially helps tend the farm during what appears to be a highly successful summer harvest. Her mind becomes affected by the strange environment, causing her to withdraw from her family.

Thaddeus is the oldest son of the Gardner family. He experiences the same strange winter and subsequent mutations as the rest of the household. The shifting environment eventually affects his mind, leading to his confinement in the attic.

Merwin is the second son of Nahum Gardner. He helps his family with daily chores, including the vital task of drawing water from the property's old well.

Zenas is a son in the Gardner family. Like his brothers, he is trapped on the property as the strange blight spreads, becoming dangerously close to the old well near the meteorite crash site.

This trio of professors travels to Arkham to study the strange meteorite. They approach the anomaly with rigid academic frameworks, hastily breaking a glassy bubble found inside the rock. They quickly lose interest when the artifact behaves outside their conventional understanding.