The town or state where Clay Waller's plantation is located is never mentioned. A young female slave like Sarny has not been educated nor is she free to travel so she has no knowledge of geography, but she has years of experience with the claustrophobic world of the plantation. It is a small world bounded by the fields where the crops are worked, the communal shack where the slaves eat, and the house where the Wallers live. It is a world cruelly divided between races: the white Waller family who live comfortably and rule despotically, and the black families who are forced to live primitively but chafe constantly at their bondage.

The atmosphere of the novel is dark, literally and figuratively. Literally the world of Nightjohn is dark because much action occurs at night when slaves are free of supervision and the teaching of reading and writing can...