Brian is an eleven-year-old boy who attends weekly speech therapy for a harelip. He collects baseball cards with his father and maintains an innocent, good-hearted nature. As the first customer to enter Needful Things, his desire for a rare Sandy Koufax baseball card introduces him to the shop's unique payment system, requiring him to perform a mischievous act in exchange for his prize.

Leland is the enigmatic, sharply dressed older man who opens the new antiques store, Needful Things. He possesses an uncanny ability to immediately identify the deepest material desires of his customers, offering them prized items in exchange for small amounts of cash and the promise to play pranks on their neighbors. He maintains a polite, sophisticated veneer that masks a deeply sinister agenda.

Polly is a middle-aged woman who owns and operates the local sewing shop. She experiences constant, debilitating pain from severe arthritis in her hands, which threatens her livelihood and independence. Having returned to Castle Rock after a difficult period in San Francisco, she keeps secrets about her past while finding comfort in her budding relationship with the local sheriff.

Alan is the sheriff of Castle Rock, a sturdy law enforcement officer currently grappling with severe grief and depression. He lost his wife and young son in a tragic car crash and constantly wonders about the exact circumstances of the accident. He relies on sleight-of-hand magic tricks to connect with children and ease his anxiety while striving to maintain order in a town prone to petty squabbles.

Nettie works in town and is a close friend to Polly Chalmers. She lives a largely isolated life marked by paranoia, stemming from her dark history of killing her abusive husband in self-defense. She is extremely protective of her dog and finds herself drawn to a piece of carnival glass at Needful Things that makes her feel a sense of wholeness.

Wilma is an aggressive, hot-tempered resident of Castle Rock who views all relationships as constant battles for dominance. She frequently terrorizes her husband and harbors an intense annoyance over the barking of her neighbor's dog, waiting for an excuse to escalate the conflict.

Dan is the Head Selectman of Castle Rock and controls the town's finances. He harbors a severe gambling addiction that has led him to embezzle public funds for years. His guilt manifests as intense paranoia, causing him to believe a shadowy group called The Persecutors is monitoring his every move.

Hugh is a local resident struggling with severe alcohol addiction. His days consist largely of drinking binges, leaving him disconnected from his surroundings until he spots a nostalgic fox-tail in the window of Needful Things, which triggers a powerful obsession.

Sally is a speech therapist at the local school and a devoutly religious woman. She is engaged to the high school physical education coach but remains a subject of local gossip due to her previous relationship with a town deputy. She desires a wooden splinter supposedly originating from Noah's Ark.

Lester is the high school physical education coach and Sally Ratcliffe's fiancé. He is deeply devoted to Sally but harbors intense jealousy regarding her past relationships, making him susceptible to suggestions that she might be unfaithful.

Cora is Brian's mother, a woman who spends most of her days eating chocolate and watching soap operas. She becomes entirely consumed by the arrival of Needful Things, specifically desiring merchandise related to Elvis Presley to fuel her elaborate fantasies.

Myra is Cora Rusk's best friend and shares her intense infatuation with Elvis Presley. Their friendship is tested when they both spot a rare photograph of the singer in the new shop, sparking a fierce, quiet competition to acquire it first.

Ace is an infamous Castle Rock criminal with a long history of drug dealing and causing trouble. He returns to his hometown desperate to find a way to pay off an enormous debt owed to dangerous gangsters, hoping his deceased uncle left behind hidden wealth.

Norris is a deputy working under Sheriff Pangborn. He is a diligent but emotionally vulnerable officer who misses his deceased father. He spots a fishing rod at Needful Things that reminds him of his father, making him eager to strike a deal with the proprietor.

Myrtle is the wife of the town's Head Selectman. She lives in a state of constant anxiety and depression due to her husband's verbal and physical abuse, finding small comforts in shopping and attempting to appease his unpredictable moods.

Sean is Brian's younger brother. He looks up to Brian and becomes increasingly worried as his older sibling's behavior grows secretive following visits to the new shop in town.

John is a deputy in the Castle Rock sheriff's department. He continues to carry a torch for his ex-girlfriend, Sally Ratcliffe, keeping a photograph of her in his wallet despite her engagement to another man.

Pete is Wilma's husband. He attempts to manage his wife's explosive temper by secretly slipping anti-anxiety medication into her tea, preferring to quietly sedate her rather than face her wrath directly.

Frank is the middle school principal who harbors dark, illicit secrets regarding his attraction to underage boys. He is deeply protective of his professional reputation and fears exposure.

George is the middle school wood shop teacher. Like the principal, he hides disturbing secrets and illegal materials in his home, maintaining a fragile, suspicious alliance with his colleague.