Marjorie is a 20-year-old aspiring fashion designer living in Grosse Pointe, Michigan. Born into a wealthy automotive glass dynasty, she possesses a creative spirit that repeatedly clashes with her family's demand for strict social propriety. Her sewing machine serves as her primary tool for expression, allowing her to turn fabric scraps into striking garments, including a highly controversial tree-inspired tunic. Seeking refuge from her father's disapproval and threats of disciplinary action, she secretly attends a women-only arts residency in Detroit called the Nightingale.

Graham is Marjorie's loyal brother who provides a crucial buffer between her and their father. He continues to wear an eye patch long after a severe eye injury, keeping it as a visible, silent reminder of the damage caused by a champagne cork their father aimed at him. Highly aware of the corruption and instability beneath the family's respectable veneer, he secretly writes obituaries with his sister Chet to earn independent income while covering for Marjorie's absence.

Chet is Marjorie's older sister, characterized by her sardonic humor and morbid fascination with death. Driven by the lingering trauma of finding her mother's body as a child, she channels her dark interests into writing obituaries that she submits to the local newspaper under Graham's name. She acts as a fiercely protective force for Marjorie and actively seeks ways to undermine their father's authority at the Glen Arden estate.

Charles is a wealthy Grosse Pointe bachelor who sponsors the Nightingale arts residency in Detroit. He maintains a highly secluded lifestyle, utilizing a private entrance and keeping unusual hours that fuel intense speculation among the residents. Years earlier, he guided a young Marjorie away from a dangerous fire at a hotel, an act of quiet protection that left a lasting impression on her.

Duncan currently controls the Lennox automotive glass dynasty and demands unwavering adherence to high-society expectations. He views Marjorie's artistic nature and unconventional public behavior as a direct liability to his business interests, frequently threatening to send her away for strict discipline. His desire for control dictates his professional dealings and creates a volatile environment at the family estate.

Cecile is Duncan's eldest child and heavily favors the material comforts provided by her family's wealth. She is preparing to host a major housewarming party at her lavish new Detroit Golf Club estate, an event designed to solidify her social standing. She frequently clashes with her younger siblings, preferring to align herself with their father's demands for respectability.

Ivy is a glamorous, highly eccentric painter living at the Nightingale residency. She exclusively paints vibrant Christmas scenes, referring to her ongoing series as "Tuesday Christmas." She quickly befriends Marjorie upon her arrival, bringing a lively and slightly chaotic energy to the otherwise heavily regulated building.

Bernice is a practical, hardworking furniture architect from Michigan's Upper Peninsula. As a resident at the Nightingale, she takes her craft seriously, experimenting with bent plywood to design innovative chairs. She becomes the first person to treat Marjorie's fashion ambitions with genuine professional respect, offering her steady encouragement.

Cormac is the aging patriarch who originally built the Lennox family fortune in the automotive glass industry. He stubbornly refuses to leave Glen Arden, the estate he built, and takes legal precautions to prevent Duncan from forcing him out of power. He maintains a quiet but sharp awareness of his grandchildren's secrets and struggles.

Lilah is Duncan's current wife and Marjorie's mother. While she publicly plays the role of a conventional, obedient society wife, she privately hides cash in a secret "play fund" inside her dressing table. Her actions and occasional telegrams complicate Marjorie's attempts to hide her true location at the arts residency.

Lou works closely with his father-in-law at the Lennox glass factory and enjoys a wealthy lifestyle in Grosse Pointe. He frequently conducts business with individuals connected to Detroit's criminal underworld, comfortably mixing legitimate enterprise with illicit connections.

Juliette is Charles Bonafante's sister and the owner of the Nightingale building. She operates quietly behind the scenes, possessing significant influence over the structure and rigid rules of the residency program while remaining out of sight of the residents.

Dock is the stern manager of the Nightingale residency who runs the daily operations from his basement office. He rigidly enforces the building's lease, issuing demerits for any rule infractions and ensuring the heavy doors are bolted strictly by the 9 pm curfew.

Hank initially appears at the Nightingale as an overly curious newspaper delivery boy. Marjorie soon deduces that he is actually a cub reporter, the son of a chief editor, who is aggressively investigating Charles Bonafante and the Lennox family to advance his journalistic career.

Peter is an artist and Marjorie's former beau. Following his involvement in a severe, highly publicized scandal regarding a jewel theft at the Detroit Institute of Arts, he abruptly disappeared from Marjorie's life under strict orders from her father.

Granny is the matriarch of the Lennox family and Cormac's wife. She possesses a sharp, cynical wit and frequently points out the family's toxic dynamics with dark humor, though she maintains genuine affection for her grandchildren.

Georgina is a highly reclusive playwright occupying the red-doored apartment at the Nightingale. She works frantically to meet a strict deadline and relies on eavesdropping on the other residents to gather dialogue and material for her characters.