Ruby is a sixteen-year-old girl imprisoned for six years at Thurmond after developing mysterious abilities following a deadly pandemic. She hides her true identity as an "Orange"—a feared classification with the power to control minds—to survive the brutal camp conditions. She acts resourcefully but deeply fears her own abilities, actively avoiding using them. She constantly worries about accidentally hurting others while still wanting genuine human connection.

Liam is a teenage boy with telekinetic "Blue" abilities who serves as the informal leader of a small group of runaway Psi teens. He speaks with a southern accent, wears a leather jacket, and easily draws people to him with his easygoing, empathetic nature. Driven by a sense of responsibility, he carries heavy guilt over the kids who died during their breakout from the Caledonia camp.

Chubs is a highly intelligent teenager with poor eyesight and "Blue" abilities. He acts as the protective cynic of the group, deeply skeptical of newcomers and adult-run institutions. He often reads a copy of Watership Down and values critical thinking above blind trust. Despite his abrasive exterior, he remains fiercely loyal to his friends.

Zu is an eleven-year-old girl with "Yellow" abilities who refuses to speak following her experiences at the Caledonia internment camp. She wears rubber gloves to suppress her electricity manipulation powers out of fear of accidentally hurting someone. She eagerly seeks female companionship and slowly rebuilds her confidence through her friendship with Ruby.

Clancy is the teenage son of President Gray and the leader of the East River community, often called the "Slip Kid." As one of the rare surviving "Oranges," he possesses powerful mental abilities and offers to teach Ruby how to control hers. He runs the camp based on his personal judgment rather than strict rules, creating an environment where Psi kids live freely away from government forces.

Cate is a young doctor associated with the Children's League who smuggles Ruby out of Thurmond. She frequently smells of rosemary, a scent that triggers deep memories for Ruby. She offers Ruby kindness and advice on survival, though her ties to a militant organization introduce complications to their dynamic.

Martin is a teenage boy and fellow "Orange" who escapes Thurmond at the same time as Ruby. Unlike Ruby, he enjoys using his abilities to manipulate the emotions of others, making those around him highly uncomfortable with his lack of personal boundaries.

Rob is an operative for the Children's League who travels with Cate. His violent past actions and intimidating demeanor immediately trigger Ruby's survival instincts, leading her to flee their company.

The President of the United States who extended his own term using wartime powers. He oversees the government's harsh response to the surviving Psi children, implementing the camp system while falsely holding his own son up as proof of successful rehabilitation.

Sam is a "Green" inmate at Thurmond who becomes Ruby's best friend. Their years of shared hardship in the camp are tragically severed when Ruby's emerging powers accidentally erase her memories of their friendship entirely.

A relentless, British-accented skip tracer who tracks runaway Psi teens. She persistently hunts Liam and his friends across the country in hopes of collecting a government bounty.

A well-liked former friend of Liam and Chubs from the Caledonia camp who died during their breakout. His memory profoundly influences his surviving friends, who carry a letter he wrote for his father.

Ruby's beloved grandmother, also named Ruby. She represents one of the few pure, happy memories from Ruby's life before the camps, remaining a vital symbol of safety and hope.

A Psi teenager from the Caledonia camp who now lives at East River. He conducts supply runs for the camp and helps integrate Liam's group into the community.

A "Green" Psi teenager and Zu's cousin. Her presence at East River provides Zu with a much-needed connection to her biological family and a voice, as Hina often speaks for her.

The leader of a small group of runaway Psi teenage boys living in a dilapidated Walmart. He is overly aggressive, makes Ruby deeply uncomfortable, and is willing to barter information for his own safety.

Liam's older brother who became involved with the Children's League. His involvement with the militant organization strained his relationship with Liam, who strongly disliked the violent effect it had on him.

Liam's younger sister who contracted the devastating Idiopathic Adolescent Acute Neurodegeneration (IAAN) illness. Her implied death deeply affects Liam's protective nature toward other children.

A teacher and Ruby's mother who lives in Salem, Virginia. Her memory is accidentally erased by Ruby, leading her to treat her own daughter as a complete stranger and call the police.

A police officer and Ruby's father. After his memory of Ruby is accidentally wiped by her developing powers, he treats her like an unknown intruder in their home.

A trauma surgeon from the Washington D.C. area. He communicates with his runaway son through cleverly coded online book reviews.

A former employee for the Department of Defense who lost her job while attempting to protect her Psi-positive son from government internment.

Zu's biological father. Out of fear of her newly developed Yellow abilities, he and his wife turned their young daughter over to the government authorities.

Zu's biological mother. Terrified by the emergence of Psi abilities, she participated in sending her daughter to the Caledonia internment camp.

A member of the security team at the East River camp. He strictly enforces Clancy's rules and orders, participating in the physical detention of anyone attempting to leave without permission.

A teenage resident of East River who works on the night security watch alongside Liam. She assists in bringing Liam back to his cabin after he is injured.

A teenage girl residing at the East River camp. She works organizing supplies and is occasionally used by camp leadership to pass messages.