Marigold is a Black high school junior and former track star who recently relocated from California. Following a traumatic experience with laced marijuana that nearly cost her her life, she is recovering from addiction and trying to earn back her family's trust. She struggles with intense anxiety and delusional parasitosis, an obsessive fear of bedbugs stemming from a past infestation in her childhood home.

Raquel is a Black writer who recently secured a three-year artist-in-residency with the Sterling Foundation. The grant provides her blended family with rent-free housing in a renovated Maplewood property, offering them financial relief after Marigold's expensive rehabilitation. She desperately wants her new marriage to succeed and works hard to keep peace in the household.

Alec is a white financial analyst who recently married Raquel. He secured a new job through a partner firm of the Sterling Foundation, prompting the family's relocation to the Midwest. He is fiercely protective of his daughter and quickly dismisses the deteriorating conditions of their new neighborhood as the fault of local street criminals.

Yusef is a high school junior and longtime Maplewood resident who helps run his uncle's yard care service. He is an aspiring DJ who holds a strict personal ban on drug use because his father is serving time in prison on possession charges. He shares an interest in community gardening and introduces Marigold to the neighborhood's history.

Mr. Sterling is the wealthy director of the Sterling Foundation, an organization claiming to revitalize the impoverished Maplewood area. He presents himself as a philanthropic savior, yet his aggressive push for high-end redevelopment heavily displaces the local residents. He frequently checks in on the Anderson-Green family, ensuring they comply with the terms of their residency.

Sammy is Marigold's middle-school-aged younger brother. He is highly observant and quickly notices the strange smells and eerie occurrences in their new house. He suffers from a severe, life-threatening peanut allergy that requires him to carry an EpiPen at all times.

Piper is Alec's ten-year-old daughter. She actively rejects her new stepfamily, using lies and tattling to create conflict between Marigold and Alec. She claims to have an imaginary friend who lives in the house, blaming this entity for missing items and strange occurrences.

Ms. Suga is an entity that ten-year-old Piper claims is her "imaginary friend." According to Piper, Ms. Suga is an older Black woman who previously owned the house and intensely dislikes Marigold. As strange smells, missing items, and eerie voices plague the property, Marigold begins to fear that Ms. Suga is a malicious ghost.

Jon Jon is a historical figure from Cedarville's past. He was the youngest son of the Peoples family, who originally owned the Anderson-Greens' current house. Local lore states that an angry mob of neighbors set fire to his home next door, a tragic event that sparked the destructive neighborhood tradition known as "Devil's Night."

Erika is a student at Kings High who quickly befriends Marigold. She lives with her grandmother because her father and brothers are currently incarcerated in the local for-profit prison. She provides Marigold with a link to the local social scene but also tempts her to break her sobriety.

Tamara is Marigold's best friend from her old life in California. Despite the physical distance, she acts as Marigold's primary sounding board, offering advice, mailing her seeds, and helping her research the strange occurrences in Cedarville via video chat.

Mr. Watson is the supervisor of the construction crew hired by the Sterling Foundation. He is visibly tense while working on the Maple Street property, constantly asks about missing tools, and absolutely refuses to let his men enter the basement.

Chay is Marigold and Sammy's biological father. He works as a contract architect currently stationed in Japan, meaning he can only offer long-distance support to his children as they adjust to their new life in the Midwest.

Mr. Brown is Yusef's uncle and a longtime Maplewood resident. He runs a local landscaping business and serves as a protective guardian figure for his nephew and elderly father.

Pop Pop is Yusef's grandfather. He is an elderly Maplewood resident who spends much of his time ordering "holy seeds" from a predatory televangelist hotline, reflecting the neighborhood's vulnerability to outside scams.

Reverend Clark is a popular local televangelist who broadcasts across Cedarville. He preaches about planting "holy seeds" and asks his economically struggling viewers to send him donations in exchange for these supposed blessings.

Irma is a representative from the Sterling Foundation who manages Raquel's artist-in-residency onboarding. She exhibits a surprisingly cold demeanor and issues strict, ominous warnings about keeping the house's basement locked.

Bud is the Anderson-Green family dog. He usually sleeps in Marigold's room and is highly sensitive to the strange smells, noises, and unseen presences in the Maple Street house.