Graham is a fourteen-year-old skilled driver who ends up in the Jerome Atchison Juvenile Detention Center after a botched robbery. He possesses a natural talent for handling cars that brings him comfort, though he often relies on "not thinking" to avoid dealing with the consequences of his actions. Given a second chance at Douglas Healy's halfway house, he attempts to balance high school chemistry classes and community service at a local business improvement district.

Arjay is a towering, fifteen-year-old teenager sent to a medium-security adult prison after a tragic altercation with bullies. Despite his imposing physical size and the dangerous reputation forced upon him by the justice system, he is fundamentally kindhearted and responsible. He plays Led Zeppelin's "Stairway to Heaven" on his guitar to manage the stress of his incarceration, eventually taking this musical passion into the city.

Terence is a troubled teenager from Chicago who believes his survival depends on aligning himself with a powerful street crew. Coming from an abusive household, he constantly searches for loyalty and protection in the wrong places. Initially resistant to the strict rules of the halfway house, he sneaks out onto the fire escape and skips mandatory activities to associate with local gang members.

Douglas is a reformed juvenile delinquent who has built a successful, respectable life and wants to offer the same opportunity to others. He secures an apartment in New York City and establishes a strict routine of school, counseling, and community service to keep his three charges out of the prison system. He is deeply committed to giving the boys a second chance, viewing them as reflections of his own troubled youth.

DeAndre is a tough, intimidating student at Alma K. Walker High School who runs a small gang of teenagers. Recognizable by his jagged teeth and a dollar sign shaved into his hair, he projects power and demands strict obedience from his followers. He uses violence and blackmail as tools of initiation, viewing new recruits purely as assets for his criminal activities.

Roxanne is a warm, well-liked teenage volunteer at the Yorkville hospital. Coming from a highly privileged family, she dedicates her time to volunteering as a way to give back to the community. She works in the head trauma unit and the laundry room, offering a glimpse of a worry-free existence outside the juvenile detention system.

Debra is the strict, imposing social worker assigned to evaluate Douglas Healy's experimental program. She is openly skeptical of the initiative, believing that troubled youths should remain incarcerated to protect society. She conducts spontaneous apartment inspections and searches for any violation, such as sharp objects or broken curfews, to justify shutting the project down.

Casey is a teenager with blue hair, a tongue-stud, and a punk rock aesthetic who attends Dr. Avery's therapy group. She has a dark sense of humor and frequently discusses her preferred ways to die during sessions. She is perceptive about the boys' excuses for their crimes and quickly takes an interest in Arjay's musical talent.

Mrs. Liebowitz is an elderly woman living in the same apartment building as the halfway house program. She is initially furious about juvenile offenders moving into her building and rebuffs any attempts at neighborly peacemaking. She closely monitors the boys' activities from her apartment, ready to report any suspicious behavior.

Dr. Avery is a strikingly beautiful psychotherapist who runs the mandatory group counseling sessions for at-risk teenagers. She facilitates discussions among the youths, attempting to bridge the gap between minor offenders and teenagers with serious criminal records. She commands respect from the group, easily handling their deflected questions and defensive attitudes.

Reuben is Graham's older brother whose criminal activities directly lead to Graham's placement in the juvenile detention system. He uses his younger brother's exceptional driving skills to operate stolen getaway vehicles, exploiting Graham's loyalty for his own financial gain before being sent to an adult prison.

Mike is the deputy chief of police in New York City and a close associate of Roxanne Fitzner's wealthy father. He uses his position and authority within law enforcement to monitor the social circles of his friend's daughter, ensuring she does not associate with people he deems inappropriate or dangerous.

Diego is a quiet student at Alma K. Walker High School who lives in constant fear of being bullied by his larger classmates. When Graham is assigned to sit next to him, Diego is visibly terrified of the new student's juvenile detention record, though the two eventually share an unspoken understanding about the harsh realities of their school environment.

Mr. Cantor is the music teacher at the high school who discovers Arjay playing the guitar alone. Recognizing the teenager's immense talent and emotional connection to music, he offers to give him private lunchtime lessons when Arjay's halfway house restrictions prevent him from joining the official after-school stage band.

Kellerman is a counselor from the Lion's Head Island alternative detention program. He processes Terence's transfer to the new halfway house in New York City but remains deeply cynical about the teenager's capacity for reform, warning others that Terence will inevitably betray anyone who tries to help him.

Drew is a teenager attending Dr. Avery's group counseling sessions. He is in trouble for illegally downloading music on behalf of his older brother, a relatively minor offense that highlights the clear differences between the everyday suburban teenagers in the group and the hardened halfway house residents.

Victoria is a teenager in the mandatory group counseling sessions who is working through issues related to shoplifting. Her casual attitude toward theft frequently triggers discussions among the other youths regarding the severity of their various crimes and the consequences they face.

Goliath is a large, intimidating bully at Alma K. Walker High School who frequently targets smaller, fearful students. He uses his size to dominate the cafeteria and hallways, operating with impunity until he encounters students who refuse to be intimidated by his aggressive tactics.