Content Warning: This section discusses child abuse, sexual abuse, and cannibalism.

Butcher & Blackbird explores the complicated ethics of vigilante justice through the protagonists, Sloane and Rowan, who both specialize in killing serial killers and people who commit other heinous acts such as child abuse. Both protagonists feel that they render the world a better place by ridding it of the “monsters” that they kill, although both also worry that, since they are technically serial killers themselves, they might be monsters just like their victims are. The novel calls the ethics of Sloane and Rowan’s actions into question but ultimately postulates that their noble motivations outweigh the moral problems with ending a human life and the fact that both Sloane and Rowan derive pleasure from punishing others. The novel humanizes the protagonists while emphasizing the monstrosity of their victims, suggesting that the murderous actions of the protagonists are morally complex or even “good” as opposed to evil. However, the ending of the novel hints that vigilante justice has broader repercussions that Sloane and Rowan will face in the sequel.

To increase the reader’s empathy for the protagonists, the author delves into backstories detailing each protagonist’s first kill and the motivations behind it.