There was a time when the people of Greenheart, Colorado, believed they were living in a town on the rise and a promised land of plenty. But by 1936 Greenheart is choking on biblical plagues of dust storms, locusts, and drought. Even once-thriving farming families like the Thorpes—Tom, Emily, and fourteen-year-old Will—are coming apart at the seams.

Enter Gideon Starling, a charismatic stranger who promises to stop the dusters and bring rain back to Greenheart’s parched fields—for a price. Aided by young Will’s work as his local guide and secret informant, the silver-tongued rainmaker attracts acolytes like moths to the flame. But Will’s starstruck admiration for his raconteur of a boss curdles into something approaching fear as Gideon’s courtship of Greenheart takes increasingly strange and sinister turns. But what game is Gideon playing? And what are the true stakes for Will, his parents, and Greenheart itself? Only Gideon seems to know.

As Gideon’s implacable charm campaign draws the desperate people of Greenheart ever closer to a mysterious abyss, Will descends into the pitch-black catacombs of the rainmaker’s past in search of redemption—and answers to the questions haunting his every waking moment. Is Gideon the savior Greenheart has been waiting for? A sociopathic grifter intent on engineering the town’s destruction? Or something worse?