Alice is a petite teenager living with her foster mother in a quiet town. Behind her polite, normal exterior, she hides her true identity as Jennifer Jones, a child who was convicted of killing her friend six years ago. Currently attempting a fresh start, she experiences intense paranoia that someone will recognize her and destroy her new life. She carries heavy trauma from her unstable childhood and desperately wants to prove she can be a good person.

Carol is Jennifer's biological mother, who became pregnant at a young age and is ill-equipped for parenthood. She works sporadically as a model but struggles to maintain steady employment or provide a secure home. Vain and frequently desperate for money, she neglects her child's emotional needs and drifts into increasingly compromised career choices, frequently abandoning her daughter with acquaintances or relatives.

Rosie is Alice's dedicated and supportive foster mother. She represents the nurturing and stable maternal figure that Alice lacked during her early childhood. She helps Alice navigate daily life and covers for her when the threat of discovery looms, rarely going out in order to prioritize Alice's safety.

Frankie is a local university student dating Alice. Initially appearing somewhat impatient and protective regarding their relationship, he genuinely cares for her and integrates her into his warm, supportive family life in Brighton. He remains entirely unaware of her traumatic past early in their relationship.

Michelle is Jennifer's childhood best friend and next-door neighbor. She is bossy, assertive, and likes to dictate the terms of her friendships. She forms a tight but conflicted bond with Jennifer, alternating between treating her as an ally and excluding her.

Lucy is a shy, reticent neighborhood girl who is a few years younger than Michelle and Jennifer. She often tags along with the older girls, alternating between being included in their games and being the target of their bullying. Her own home life is complicated by her mother's poor health and her absentee father.

Sonia is a student at Jennifer's elementary school. She briefly aligns herself with Michelle during one of Michelle's arguments with Jennifer, becoming a target of Jennifer's frustration.

Mr. Cottis is a sneaky and untrustworthy photographer who employs Carol. He draws Carol into shady, pornographic photoshoots for money and attempts to involve her young daughter in his exploitative work.

Sara is a woman who moves into the apartment below Alice and Rosie. While she presents herself as a friendly neighbor and elementary school teacher, she is secretly an investigative journalist attempting to gain exclusive access to Alice's hidden life for a national newspaper.

Jill is the woman in charge of Alice's case. She works tirelessly to manage Alice's transition back into society, organizing resources like mobile phones and strategies to deflect media attention away from her client.

Patricia, or "Pat," is a worker at Monksgrove, the facility where Alice lived after being found guilty. She assists in managing Alice's file and helps coordinate the plans to ward off the press.

Derek is a freelance detective hired to track down Jennifer Jones. He frequents the area around the coffee shop where Alice works, causing her immense stress as he gets dangerously close to discovering her secret.

Sophie is Frankie's ten-year-old sister. She is bubbly and welcoming, enthusiastically bringing Alice tea and inviting her to play games with the family. She represents the innocent childhood Alice never experienced.

Steve is Lucy's older brother. He is obsessed with the military and often wears camouflage outfits. He frequently mocks Jennifer's mother, contributing to Jennifer's anger and alienation.

Joe is Lucy's other older brother. He enjoys military games and building secret hideouts in the local woods alongside Steve, operating largely without adult supervision.

Kathy is Rosie's mother. She treats Alice kindly and shares coffee with her daughter and foster granddaughter, discussing plans to vacation at her house in Majorca.