Dark Mill South is the primary antagonist, a round but static character who functions as a seemingly supernatural force of vengeance. His backstory, detailed in an encyclopedic, almost mythic fashion, establishes him as a legendary serial killer known by many names, including “the Nomad” (12). His character is the novel’s most direct embodiment of Historical Trauma as a Perpetual Cycle of Violence. An Ojibwe man, his stated mission is to kill 38 people to “balance the scales” (14) for the 38 Dakota men executed by the US government in 1862. This motivation roots his contemporary rampage in unprocessed historical atrocity, suggesting that his violence is a grim form of justice delivered to a society that has failed to reckon with its past.

Dark Mill South’s characterization blurs the line between a human killer and a folkloric monster. At an imposing six-and-a-half feet tall, with a hook for a hand and a face of “knotted scar tissue” (15), he fits the archetype of the quintessential slasher villain. The theatricality of his appearance connects him to the novel’s meta-commentary on the horror genre, suggesting that the violence plaguing Proofrock is shaped by both historical precedent and fictional tropes. He is less a psychological study and more a symbol of a brutal, inescapable past that continues to haunt the present, a “rough beast” (9) whose violence is as relentless and indifferent as the blizzard that isolates the town.

Letha Mondragon-Tompkins serves as a deuteragonist and a foil to Jade, undergoing a significant dynamic transformation from a survivor of the Independence Day Massacre to a proactive and prepared fighter. A round character, Letha’s trauma is physically manifested in her reconstructed jaw, a constant reminder of the violence she endured. In response, she has methodically studied the slasher genre, the very field that was once Jade’s obsession, to arm herself with knowledge. This intellectual preparation is paired with practical readiness; she is a woman who now thinks to equip herself with steak knives as weapons. Letha’s evolution represents a conscious act of self-determination, refusing to remain a passive survivor and instead taking control of her own survival narrative.

Letha’s partnership with Jade is fundamental to the novel’s exploration of female solidarity. Where the classic slasher film isolates its final girl, Letha and Jade find strength in their alliance, repeatedly protecting and rescuing one another. This bond reframes survival as a collective effort rather than an individualistic one, directly challenging a key tenet of the genre. Her decision to name her daughter Adrienne, after the actress who played the final girl in Friday the 13th (66), signifies her full integration of the slasher ethos into her identity as a mother and protector. She has repurposed the genre’s rules from a source of fear into a practical guide for defending her family, embodying a new, more resilient model of survivorship.

Cinnamon and Ginger Baker are secondary antagonists whose subterfuge is necessary for building the theme of The Instability of Truth and Narrative. The novel continuously hints that one of the Baker sisters is impersonating the other, but remains purposefully ambiguous on which sister is which, so as to build tension and mystery around their intentions.

The novel initially distinguishes the twins by presenting Cinnamon as the survivor of South’s initial attack, making her a potential new “final girl,” and Ginger as a long-term patient in assisted living who has removed her hair. In Chapter 15, however, the Baker girl who appears at the sheriff’s office loses her wig, which convinces Jade and her allies that Ginger has left the hospital and is posing as Cinn. Towards the end of the novel, it is suggested that the reverse is also true: Galatea’s discovery of wigs in Cinn’s room suggests that she may be posing as Ginger as the blizzard passes through Proofrock. This act of deception is a powerful physical manifestation of the novel’s exploration of masks and disguises, showing how identity can be a fluid and dangerous construct. The backstories and personas both Baker sisters present therefore prove to be unreliable narrations, forcing a complete reinterpretation of events once the truth of their identities are revealed.

Ginger’s motivation is rooted in a deep-seated resentment toward Cinnamon, whom she blames for abandoning her during the Terra Nova massacre on the yacht years earlier. Her desire is not just for revenge but for usurpation; by killing Cinnamon and stealing her identity, Ginger attempts to seize the life she believes she was denied. Likewise, it is suggested that Cinnamon wants to take revenge against her peers for spreading rumors of her illicit affair with her history teacher, Claude Armitage. Galatea is the only person who intuits that Cinn was abused since she witnesses Cinn’s suicidal ideation. These motivations drive a deconstruction of the singular final girl archetype, especially once it is implied that Cinn planned to frame Dark Mill South for her murders and turn herself into the final girl who defeats him. Their parallel acts of subterfuge blur the lines of responsibility for the murders, further destabilizing any sense of clear-cut good and evil in Proofrock.

The former sheriff of Proofrock, Angus Hardy, functions as a mentor and paternal figure for Jade. He is a round, static character whose present is inexorably shaped by the trauma of his past. The drowning of his daughter, Melanie, years ago has defined his existence, and his current post as the dam-keeper is a self-imposed penance that keeps him physically close to the site of her death. This personal history of loss makes him empathetic to Jade’s own trauma, and he is one of the few adults in her life to offer unwavering belief and protection. The physical impact of his injuries sustained in the Independence Day Massacre stands in contrast to his sharp mind and steadfast moral compass, making him a symbol of the town’s wounded but enduring conscience.

Hardy’s relationship with Jade is one of mutual respect and quiet understanding. He recognizes her intelligence and resilience beneath her abrasive exterior and provides her with the guidance and validation she rarely receives from others. As one of the few people who has always been in her corner, he represents a link to a more stable, albeit still tragic, past. His presence at the dam, overlooking the town and the lake, gives him a unique vantage point, both literally and figuratively. He is a keeper of memories, both the town’s and his own, and his wisdom serves as an anchor for Jade as she navigates the new cycle of violence engulfing Proofrock.

Deputy Banner Tompkins is a significant secondary character who represents the overwhelmed and inadequate official authority in Proofrock during the blizzard. A round and somewhat dynamic character, Banner begins the story as a probationary deputy who is clearly out of his depth, constantly awaiting the return of his superior, Sheriff Allen. His initial interactions with Jade are tinged with the condescension of their shared high school past, but as the violence escalates, he develops a grudging respect for her expertise and courage. His primary motivation is the protection of his wife, Letha, and their daughter, Adrienne, a responsibility that often conflicts with his duties as an officer, highlighting his struggle between personal and professional obligations.

Banner’s development is marked by his gradual transition from an insecure young deputy into a man forced to take decisive, even heroic, action. Initially portrayed as somewhat hapless, referring to Jade’s mother and father by saying, “your mom, your dad” (41) as if it’s a source of shame, he is ultimately the one who takes down Dark Mill South by ramming him with a snowplow. This act is the culmination of his character arc, transforming him from a follower into a leader who takes responsibility for the safety of his town. He embodies the ordinary person thrust into extraordinary circumstances, rising to the occasion through sheer determination to protect his family and community.

Galatea Pangborne is a minor character who serves a unique narrative function as an in-world academic and analyst. A round and static character, Galatea is a high school student who writes with a detached, scholarly voice, authoring essay-like chapters that frame and interpret the events of the novel. Her chapters, which are given titles like ‘A History of Violence’ and ‘Her Name Was Jade,’ provide context for Proofrock’s cycle of trauma and offer theories on character motivations. This meta-narrative makes her a modern version of a Greek chorus, commenting on the tragedy as it unfolds. Her presence reinforces the theme of The Instability of Truth and Narrative, as her analyses are presented as just one more layer of storytelling, a subjective interpretation rather than objective fact. She also drives the novel’s themes on female solidarity at the end of the novel when she weaponizes history to avenge Cinn, blackmailing her history teacher Claude Armitage when she realizes that he sexually abused Cinn.