The Story of Edgar Sawtelle is primarily allegorical and is said to be based on William Shakespeare's play Hamlet; Edgar himself, the allegory of the eponymous Prince of Denmark, is admittedly Shakespearean, but his story could just as easily appear on any episode of Forensic Files or in suspense-filled psychological drama novel because of its enduring themes of sibling rivalry, jealousy, avarice and murder.
The chief antagonist is Edgar's uncle, Claude, and it is his inability to get along with his brother for most of their lives that is the catalyst for the unravelling of the Sawtelle family. An argument that would in most families mean an estrangement, or a couple of holidays spent apart, escalates in the Sawtelle family and triggers Claude's decision to murder Gar, and cover it up afterwards. Claude's entire existence revolves around covering up his actions, and the main reason for his wanting to drive Edgar out of the house is so that he won't have to take so much time or care covering his tracks, and hiding the evidence of his actions. This is also allegorical of the way in which the murder of Hamlet's father is covered up in the Bard's original version of the story.
Edgar's mother is another character who seems to have been uprooted from Medieval Denmark and transplanted in a North American dog breeding farm. An apparently loyal wife and mother, she is quickly blind to Claude's obvious involvement in her husband's murder because she is lonely, and the fact that he has stepped into the breach when needed has emphasized to her even more that her life is exponentially more difficult without a partner in it. Because of this immediate loyalty to Claude, she becomes distanced from her son, and also from her love for her late husband. She seems to spend the majority of the novel fighting with herself and trying to remain in denial about the things she knows deep down to be true. Her realization that her son is telling the truth mirrors that of Hamlet's mother in the play that bears his name, and she begins to help him prove that her new lover has killed her husband. By staying true to the Shakespearean plot, but transplating the plot line and character to a completely alien environment and time, the author manages to produce both an allegory of the original, and a completely different stand-alone family murder story.