A member of the Naturals program and Cassie’s main support who has a complex relationship with his father, a notorious serial killer. His profiling skills offer a perspective that often complements Cassie's own insights.

Another Natural, known for his emotion reading abilities, which he developed as a survival mechanism. His complex family history includes a difficult relationship with his influential and abusive father.

A profiler with an exceptional ability to detect lies, having developed her skills in a difficult childhood environment. She uses humor and sarcasm to protect herself and those she cares about.

The analytical mind of the Naturals team, known for her statistical prowess and literal understanding of the world. Her intellect often helps solve crucial parts of their cases.

Cassie’s missing mother, whose past and survival are central to the storyline. Her history is explored through Cassie's memories and the clues uncovered about a cult.

A charismatic yet incarcerated serial killer whose influence affects the Naturals, especially his son Dean. He remains a menacing presence despite being behind bars.

Michael's father, a powerful figure with a polished public persona hiding his abusive nature. His controlling behavior heavily impacts Michael's life.

Primary FBI agents responsible for managing the Naturals, who balance their professional duties with their protective instincts towards the teens. Both bring their unique skills and past experiences to their roles.

A former Marine sniper who acts as a protective guardian for the Naturals. His past losses deeply influence his commitment to the teens' safety and well-being.

Michael’s half-sister and a supporting character with sharp wit and troubled family connections, whose presence impacts the unfolding of events. Her talents provide essential insights to the team.

Cassie’s young half-sister, who is deeply affected by a traumatic upbringing in a cult environment. Her actions and knowledge significantly impact the Naturals' investigations.

A secret society of serial killers operating as the main antagonistic force. They follow a ritualistic system that embodies a corrupt and violent order.