Outer Dark is not set in a definite time or locale, but it appears to take place in the Southern Appalachian mountains during the late nineteenth or early twentieth centuries. Basically, however, the story is more like a folk tale than a realistic rendering of events, and the uncertain, sometimes nightmarish quality of the world it portrays adds to its almost surrealistic style. The book tells the story of Rinthy and Culla Holme, a sister and brother who live together in an isolated mountain cabin. Although McCarthy indicates their poverty and lack of learning, he is more interested in their moral state than in their social or economic condition.