Tiffany is a 28-year-old writer living in New York who uses various aliases (Ani, TifAni, Finny) to manage her public persona carefully. Driven by a fierce desire for security and status, she works tirelessly to maintain the illusion of a perfect life. Beneath her polished exterior, she wrestles with deep psychological trauma stemming from her adolescence at Bradley Prep, leading to an intense internal conflict over a documentary film project.

Luke is an up-and-coming financial adviser on Wall Street and the scion of a wealthy Philadelphia family. Athletic and confident, he embodies the elite lifestyle Tiffany works hard to secure. He generally prefers a problem-free, superficial existence and strongly encourages his fiancée to move past her complicated history rather than confront it.

Arthur is a brilliant but socially awkward misfit at the elite Bradley Prep. Overweight, acne-scarred, and cynical, he refuses to conform to the school's superficial culture. He displays surprising kindness toward Tiffany when she faces ostracization, revealing a sensitive nature beneath his abrasive exterior.

Andrew is a charismatic, boyishly handsome teacher who quickly becomes a trusted figure for the 14-year-old Tiffany. He operates as one of the few adults who genuinely listens to the students, offering shelter and sympathy during moments of crisis. Years later, he reenters Tiffany's life as a married adult, complicating her current circumstances.

Dean is a wealthy, popular soccer player who rules the social hierarchy at Bradley Prep. Accustomed to a life without consequences, he uses his physical appeal and status to manipulate vulnerable classmates. He orchestrates toxic behavior among his peer group, demanding compliance and punishing those who challenge his authority.

Ben is a vulnerable student at Bradley Prep who becomes a primary target for the school's aggressive jocks. Perceived as effeminate by his bullies, he endures severe psychological and physical torment that pushes him to extreme emotional distress and endangers his life.

Nell is Tiffany's fiercely loyal best friend from college and her maid of honor. Living in New York, she provides an essential grounding presence, offering blunt advice and a safe harbor when the pressures of wedding planning threaten to overwhelm Tiffany.

Peyton is a popular soccer player at Bradley who closely follows Dean's lead. He embraces the reckless, predatory party culture that defines the school's elite social circle.

Liam is a member of the popular jock clique at Bradley Prep. While he occasionally performs small favors, his allegiance remains strictly with Dean and the toxic environment they perpetuate.

Olivia is a wealthy student who commands the top tier of the social ladder at Bradley. She hosts exclusive parties and sets the standard for acceptable behavior among the cool kids.

Hilary is a popular girl at Bradley who operates as Olivia's right hand. She uses false kindness to manipulate situations, participating eagerly in the cruel public humiliation of students who fall out of favor.

Mrs. Finnerman is Arthur's mother, a woman who carries the heavy burden of the tragedy at Bradley Prep. She insists on remembering her son's humanity and gentleness, fiercely guarding the childhood artifacts that remind her of his capacity for love.

Dr. Perkins is a forensic psychologist tasked with interviewing students following catastrophic events at Bradley Prep. Her clinical approach to questioning makes her an intimidating presence for those trying to protect secrets.

Whitney is Andrew Larson's wife. She participates in the affluent social rituals of Manhattan, unaware of the complex history between her husband and his advisor's fiancée.