Structurally, To Kill a Mockingbird is circular: the story begins where it ends. The first line of the novel introduces Jem’s broken arm, and the novel then flashes back to cover the events leading up to his accident. The narrator uses this device to provide background for the Finch family, introducing the legendary Simon Finch and his three descendants. But at this stage of the novel, the family history is treated as background information, of secondary importance to the private world of the young Finch children. In this way, the first chapter provides only a brief sketch of Atticus, whose importance increases as the novel progresses. Jem and Scout are the center of the story, filling it with their world of imagination and superstition, centered on town myths such as the curious history of Boo Radley and imaginative diversions such as acting out stories from books.
Dill dominates this early part of the novel: he is only a summer visitor, with no connection to Maycomb’s adult world. As this adult world asserts itself later in the novel, Dill fades from the story. For now, however, the novel appropriates Dill’s childhood perspective and only hints at the darker, more adult problems that will intrude on Jem and Scout. One of the central themes of To Kill a Mockingbird is the process of growing up and developing a more mature perspective on life. Correspondingly, the narrative gradually comes to mirror a loss of innocence, as the carefree childhood of this first chapter is slowly replaced by a darker, more dangerous, and more cynical adult story in which the children are only minor participants.
Boo Radley becomes the focus of the children’s curiosity in Chapter 1. As befits the perspective of childhood innocence, the recluse is given no identity apart from the youthful superstitions that surround him: Scout describes him as a “malevolent phantom” over six feet tall who eats squirrels and cats. Of course, the reader realizes that there must be more to Boo’s story than these superstitions imply. Eventually, Boo will be transformed from a nightmare villain into a human being, and the children’s understanding of him will reflect their own journey toward adulthood.