Brynn is a high school senior and aspiring journalist who recently moved back to her hometown of Sturgis, Massachusetts. She secures an internship with a true-crime show and decides to investigate the four-year-old unsolved murder of her eighth-grade teacher. Her determination to uncover the truth tests her personal connections and forces her to confront boundaries in her reporting.

Tripp is a high school senior at Saint Ambrose who struggles with the lingering trauma of finding his teacher's dead body four years ago. He comes from a working-class background and relies on scholarships to attend his prestigious private school. He works hard to earn enough money to leave his hometown, heavily burdened by secrets regarding the day of the murder.

Mr. Larkin was a young English teacher at Saint Ambrose who was murdered in the woods behind the school four years prior to the novel's events. While most students viewed him as approachable and helpful, he occasionally experienced friction with adults in the community. Before his death, he was actively investigating a theft of school fundraiser money.

Ellie is Brynn's fourteen-year-old younger sister who also attends Saint Ambrose. She is observant and sharp, often acting as a sounding board for Brynn's investigative theories. She is one of the few people completely aware of Brynn's secret true-crime internship.

Brynn and Ellie's parents. Mr. Gallagher's job transfer prompts the family's return to Sturgis. They are strict but supportive parents, insisting on paying full tuition for Saint Ambrose despite the girls previously attending on scholarship.

Nick is Brynn's uncle in his mid-twenties who is pursuing a master's degree in teaching. He currently lives with the Gallagher family and previously worked as an assistant at Saint Ambrose during the time of Mr. Larkin's murder. He strongly cautions Brynn against investigating the old crime.

Junior is Tripp's father, a hardworking man who takes on night shifts and extra jobs at hardware stores to support his son. He struggles to communicate effectively with Tripp, resulting in profound emotional distance between them, but consistently works to provide a stable home environment.

Shane is a wealthy student at Saint Ambrose and part of the group that discovered Mr. Larkin's body in the woods. He skates by in school without much effort, shielded by his family's significant financial donations to the school and local police department. He maintains a surface-level friendship with Tripp.

Charlotte is a wealthy, popular student at Saint Ambrose who is fiercely attached to her boyfriend, Shane. She was one of the three students present in the woods when Mr. Larkin's body was found. She is highly protective of her social circle and actively warns Brynn to keep her distance from Tripp.

Carly is the fast-paced, quirky, and controlling head of the true-crime television series *Motive*. She hires Brynn out of amusement at the teenager's audacity and encourages her to look into the unsolved murder of Mr. Larkin, despite potential community backlash.

Gunnar is the host of a sensationalist and highly unethical true-crime show called *Don't Do the Crime*. He focuses on a narrative regarding "killer kids" connected to Mr. Larkin's murder, creating a public spectacle that negatively impacts the students at Saint Ambrose.

Regina is the owner of Brightside Bakery and Tripp's boss. She acts as a surrogate mother figure for him, ensuring he completes his college applications and maintains his responsibilities. She is stern but deeply caring, refusing to let Tripp abandon his potential.

Lisa Marie is Tripp's largely absent biological mother who lives in Las Vegas and occasionally returns to Massachusetts. She shows little genuine interest in her son's well-being, instead attempting to exploit his connection to a famous local murder for television opportunities.

Mason is a scholarship student at Saint Ambrose and one of Brynn's old friends from eighth grade. He is loyal, studious, and helps Brynn navigate the social dynamics of the school. He harbors a deep, private resentment toward Mr. Larkin.

Dexter is a pawn shop owner in New Hampshire with a reputation for being controlling and volatile. He is a deeply rigid man who becomes highly suspicious and aggressive when teenagers begin asking questions about old items connected to his past.

Mr. Solomon is the former groundskeeper at Saint Ambrose. He is elderly, lives alone in Sturgis, and becomes highly agitated when students ask him for advice about building a memorial garden for Mr. Larkin, whom he strongly disliked.

Colin is a scholarship student at Saint Ambrose who is highly critical of the school's wealthy elite. He frequently stirs up trouble by broadcasting the sensationalist Gunnar Fox videos about the murder, which often leads to physical altercations.

Nadia is a student at Saint Ambrose and part of Brynn's returning friend group. She is highly responsible, often serving as the designated driver for her friends, and helps Brynn readjust to the school's social environment.

Lindzi is Carly's assistant at the true-crime show. She gathers evidence photos and researches historical files, quietly supporting the investigation into Mr. Larkin's past even when executives attempt to shut the story down.

Officer Patz is a local policeman in Sturgis who handled the initial investigation of Mr. Larkin's murder. He continues to run into the students around town and remains involved when new police matters arise.

Rose is the owner of the Mad Dog Tavern. She is a practical woman who knows the history of the local families and provides crucial background information about a medallion connected to the murder case.