The narrator explains how he instigated a secret investigation of the ruined town of Innsmouth, Massachusetts, by the U.S. government. He proceeds to describe in detail the events surrounding his initial interest in the town, which lies along the route of his tour across New England, taken when he was twenty-one. While he waits for the bus that will take him to Innsmouth, he busies himself in the neighboring Newburyport by gathering information on the town from the locals; all of it having superstitious overtones.