Pippa is a serious, high-achieving high school senior who initially views fun as a waste of time. She struggles to choose a topic for her capstone project but discovers a natural talent for investigation during a murder-mystery game. Her strong moral compass and strict attention to detail make her a formidable problem solver.

Jamie is Connor's older brother, who orchestrates the murder-mystery game. He plays the dual roles of the victim and the police investigator, guiding the teenagers through the evening's narrative. He blurs the line between fiction and reality to create an immersive experience.

Ant is a high school classmate playing the character of Bobby Remy in the game. He treats the evening with irreverence, frequently playing jump-scare pranks on the other guests. He demonstrates a lack of tact by making repetitive, insensitive jokes about a real-life local tragedy.

Cara is Pippa's longtime best friend who provides a lighthearted contrast to Pippa's intense focus. She understands her best friend deeply and actively tries to pull her back to reality when she becomes too consumed by the game.

Connor is the host of the murder-mystery party, celebrating the end of final exams. He plays the role of Humphrey Todd, the butler, and takes his friends' phones away to ensure they remain fully immersed in the evening.

Zach is Pippa's friend and neighbor who attends the murder-mystery party, playing the role of the younger son, Ralph Remy. He engages fully in the role-playing elements, improvising business disputes and family drama to advance the game's plot.

Lauren is a friend attending the party, playing the role of Lizzie Remy. She exhibits skittishness throughout the evening, reacting to loud noises with genuine screams because she grew up in a town defined by murder.

Mr. Ward is Cara's father and a history teacher at the local high school. He acts as a surrogate father figure to Pippa and prompts her to consider her senior capstone project on the drive home.

Andie is a former high school student from Fairview whose murder continues to cast a long shadow over the town. Though physically absent, her death forms a central obsession for the community and serves as the inspiration for Pippa's academic focus.

Sal is Andie Bell's late boyfriend who is universally believed to have killed her before dying by suicide. Pippa remembers his personal kindness, causing her to harbor quiet doubts about the official narrative of his guilt.

Ravi is Sal Singh's younger brother, who continues to live in the small town of Fairview despite the immense stigma attached to his family. Seeing him walking alone at night crystallizes the reality of the town's tragedy for Pippa.