The Repairer of Reputations takes place in a near-future America, where the protagonist, Hildred Castaigne, is recovering from a head injury and becomes obsessed with a mysterious man named Mr. Wilde, who claims to restore reputations. As Hildred's delusions increase, the story delves into themes of madness, power, and distorted reality, with a dark atmosphere surrounding a forbidden play, The King in Yellow.