The Locked Door

The phrase “nature versus nurture” is used to describe the debate about the relative influence of genetic inheritance and environmental influence on human development. In The Locked Door, the question is raised as to whether Nora inherited a tendency toward violence from her father, convicted serial killer Aaron Nierling. Although Nora repeatedly insists that she is not like her father, she also seems to fear passing his genes on to her children, indicating that she does believe violence can be inherited.

Throughout the novel, Nora argues that she’s “not like [her] father” (37, 268), “not a murderer like he is” (160), and “not a monster like he is” (230). Nora uses her career as a surgeon as evidence of the difference between them, explaining that, while he murdered multiple women, “[She] save[s] lives” (37). Nora’s repeated, intentional denial of similarities between herself and her father is a reflection of her belief—and her hope—that environment can overpower genetics.

Despite these denials, Nora’s narration reveals that she worries about the genes her father passed to her. She decides not to pursue romantic relationships or build a family because they “do share the same blood” (160), and she “can’t risk passing on [her] genes to anyone else” (171). These references to blood and genes suggest that Nora believes her father’s violence is an innate, inheritable tendency that she may also possess and be able to pass on to her children. The novel suggests that this idea was planted by Nora’s maternal grandmother, who took her in after her father was imprisoned and her mother died by suicide. Nora’s grandmother repeatedly warned her, “[Y]ou have the devil in you” (134). By the time she turned 18, Nora had learned from her grandmother “what it meant to be Aaron Nierling’s daughter” (217). Nora’s fears about inheriting her father’s violence reflect a belief that a violent nature cannot be reversed by a loving environment.

In the novel’s final chapters, Harper reveals that she has been murdering Nora’s patients to avenge Aaron Nierling. She argues that, by giving into their murderous impulses, she and Aaron are being “true to [them]selves” (291) and chastises Nora for rejecting her “natural instincts” (292). Although Nora firmly and repeatedly rejects the idea that violence is “natural” to her, Harper also reveals in the novel’s final lines that Nora facilitated the murder of her patient Arnold Kellogg, who had abused his wife. This final reveal implies that, despite her protests, Nora is capable of murder like her father and sister. Ultimately, the novel suggests that certain traits—in Nora’s case, a propensity toward violence—are inherited genetically, but that Nora may be successful in overcoming this genetic propensity by building a happy life with Brady and Ruby.