Johnny is a carefree, good-natured high school teacher living in Cleaves Mills, Maine. A devastating car accident leaves him in a years-long coma, entirely halting his life and stalling his developing relationship. Upon waking, he discovers an inaccessible part of his brain he calls the "dead zone" and a new, burdensome ability to see into people's pasts and futures through physical touch. He is deeply troubled by the public attention his abilities attract.

Greg is an ambitious, charismatic politician who builds a career on anti-establishment rhetoric. He presents himself as an eccentric working-class hero, famous for wearing a construction hard hat on the campaign trail. Beneath his charming public persona, he hides a brutal temper and relies on blackmail, extortion, and intimidation to advance his political and real estate ambitions.

Sarah is a teacher who deeply appreciates Johnny's considerate and laidback approach to life. After Johnny falls into a coma shortly after they declare their love for one another, she endures years of emotional limbo. She eventually tries to move forward, marrying another man and starting a family, but her unexplored future with Johnny continues to occupy her thoughts.

Vera is Johnny's mother, a devout Christian whose son's tragic accident pushes her into extreme religious fanaticism. Desperate to find meaning in his coma, she latches onto apocalyptic cults, UFO theories, and supernatural scams. She views Johnny's psychic abilities as divine vindication of her fringe beliefs.

Herb is Johnny's hardworking father, a carpenter by trade who serves as his son's moral anchor. He drains his life savings to keep Johnny on life support and endures his wife's deteriorating mental state with quiet, miserable loyalty. He represents an ordinary man doing his best to manage extraordinary family crises.

Bannerman is the dedicated sheriff of Castle Rock, Maine. Desperate to catch a serial strangler who has murdered several women and a young girl in his jurisdiction, he reluctantly seeks out Johnny's abilities. He is fiercely protective of his community and emotionally invested in stopping the violence.

Frank is a young deputy working under Sheriff Bannerman in Castle Rock. He serves as part of the local police force actively investigating the string of gruesome murders plaguing the small town.

Dr. Weizak is one of the primary physicians overseeing Johnny's recovery at the hospital. He becomes personally invested in his patient's psychic abilities after Johnny experiences a startlingly accurate vision involving Weizak's family history in World War II Poland.

Roger is a wealthy businessman who hires Johnny as a private live-in tutor for his son. He is intelligent and pragmatic, appreciating Johnny's teaching skills while viewing political figures like Greg Stillson as entertaining novelties rather than true threats.

Chuck is a bright, athletic high school student who struggles significantly with reading. As the captain of the baseball and football teams, he requires intensive tutoring to pass his SATs and gain college admission.

Walter is a young, ambitious lawyer who eventually marries Sarah. He is highly skeptical of Johnny's public image, assuming the psychic abilities are a fraudulent scheme designed to solicit donations for hospital debts.

Dees is a reporter for a disreputable pulp magazine. He attempts to exploit Johnny's psychic reputation for profit, proposing a passive arrangement where staff writers invent predictions under Johnny's name.

Sonny is a grizzled, fascistic biker who functions as Greg Stillson's security detail and personal enforcer. He handles the physical intimidation required to maintain Stillson's corrupt operations.

Charles is a banker involved in illicit real estate deals with Greg Stillson. He is forced into acting as Stillson's campaign manager after being shown compromising photographs of a political rival.

Dr. Brown is a neurologist who treats Johnny after he emerges from his coma. Unlike his colleague, he maintains a strict, skeptical view of Johnny's visions, dismissing them as nonsense associated with brain damage.

Ngo is a Vietnamese immigrant who works as a gardener for the Chatsworth family. Removed from American political rhetoric, he easily perceives the danger lurking beneath Greg Stillson's charismatic facade, validating Johnny's fears.