Ophie is a 12-year-old girl whose life changes drastically when she relocates from Georgia to Pennsylvania following her father's tragic death. Thrust into the adult world to help support her grieving mother, she works as a caretaker for the elderly Mrs. Caruthers. Despite the oppressive environment of Daffodil Manor, she possesses a keen curiosity and a unique ability to see and speak with ghosts. She uses this secret talent to converse with local spirits and investigate the hidden histories surrounding the manor.

Clara is a striking spirit residing in Daffodil Manor, characterized by her fine clothes and kindness. She befriends Ophie early on, offering the isolated girl a bright spot in her difficult new life. Clara suffers from amnesia regarding her own past and the circumstances of her demise. She relies on Ophie to piece together clues about her history at the manor.

Mrs. Caruthers is the elderly, wealthy owner of Daffodil Manor who requires constant personal care. She exhibits extreme cruelty and prejudice, regularly belittling Ophie and creating a hostile work environment. Her miserable demeanor sets a tense tone for the household, and she grows furious at the mere mention of certain past events or names. She holds significant economic power over her staff, making her demands impossible to ignore.

Etta, known primarily as Mama, is a grieving widow forced to build a new life in Pittsburgh during the Great Migration. Burdened by the trauma of losing her husband and the pressing need to secure a stable home, she becomes strict and constantly anxious. She takes a job at Daffodil Manor and pulls her daughter out of school to work alongside her, prioritizing financial survival over emotional vulnerability. She refuses to discuss the past or acknowledge the supernatural.

Aunt Rose is Robert's relative who takes in Ophie and her mother when they relocate. Like Ophie, she possesses the rare ability to see and communicate with ghosts. She serves as an essential guide for her niece, explaining the rules of the spirit world and the lingering desires of the dead. She maintains a practical, cautious approach to the supernatural, warning Ophie to protect herself with iron and salt.

Richard is Mrs. Caruthers's son, tasked with managing the sprawling Daffodil Manor after losing his father and brothers in the war. He displays the entitlement typical of his wealthy status but lacks the overt malice of his mother. He oversees the household staff and attempts to keep peace in the home, though he harbors his own lingering grief over the disappearance of a past love.

Carol, known simply as Cook, runs the kitchen at Daffodil Manor. She serves as a grounding presence for Ophie, offering her cookies, practical advice, and moments of respite from the demanding upstairs work. Cook understands the complex, often dangerous dynamics of working for wealthy white families and shares warnings and gossip with the younger staff.

Robert is Ophie's father, a hardworking man whose attempt to vote in a local Georgia election costs him his life. His sudden, violent death catalyzes the family's migration to the North. He appears briefly to Ophie as a glowing spirit to assure her of her safety, an encounter that awakens her supernatural abilities.

Henry is the groundskeeper at Daffodil Manor. He performs his duties quietly and knows many of the estate's dark secrets. He actively discourages Ophie from asking too many questions, aiming to protect the staff from the volatile nature of their employers.

Colin is a boy ghost trapped at Daffodil Manor. He bears the physical marks of violence, having been killed while trying to run away years ago. He refuses to pass on, choosing instead to linger in the house, where he occasionally offers Ophie cryptic warnings and information about the other spirits.

Penelope is a young girl brought on to help the household staff at Daffodil Manor during a busy season. She is initially rude and demanding toward Ophie. Her presence at the manor introduces new challenges for the kitchen staff as the house prepares for important guests.

Edwina is a young white woman and a frequent guest at Daffodil Manor. She spends significant time with Richard Caruthers, representing a new chapter in his romantic life. Her presence around the house stirs up past memories for the resident spirits.

The spirit of Aunt Rose's late husband lingers in the garden of their Pittsburgh home. He tends to the flowers and fruit his wife loves, waiting patiently for the day they can be reunited. His peaceful existence offers Ophie a gentler perspective on the nature of ghosts.

Aunt Helen is one of Robert Harrison's relatives living in the cramped Pittsburgh home. She provides the grieving family with initial shelter but quickly makes it clear that they cannot rely on charity forever.

Faith is a young ghost girl trapped at Daffodil Manor. She spends her afterlife waiting for her father to come find her, oblivious to the fact that her father is also a spirit who refuses to abandon his ghostly work.

Edward is a ghost residing at Daffodil Manor who spends his time desperately looking for his missing daughter, Isabel. His relentless search keeps him tethered to the earthly plane until Ophie steps in to help him.

Isabel is a young ghost who is separated from her father, Edward, in the afterlife. She lingers in Daffodil Manor until Ophie successfully guides her and her father back to one another.

Agatha is Mrs. Caruthers's sister, visiting from Virginia. Her arrival at the manor causes significant stress for the household staff and stirs up dark memories, as she was present during Clara's mysterious disappearance years prior.

Muriel is one of Ophie's three cousins living in Pittsburgh. Instead of welcoming Ophie to her new home, Muriel and her sisters prove to be mean and exclusionary, adding to Ophie's feelings of isolation.

Gladys is an older woman hired by Richard to help the existing household staff handle the extra workload brought on by the visiting Virginia cousins. She works quietly alongside the younger servants.