Sara is a thirty-year-old head housekeeper working at a luxury hotel in 1880s London. As the illegitimate daughter of an earl and his maid, she feels alienated by England's rigid class structure and her lack of social standing. Ambitious and capable, she accepts a position across the Atlantic to manage staff at the newly constructed Dakota apartment building in New York City, hoping for a fresh start and fairer opportunities.

Bailey is a young interior designer living in 1980s New York City who recently completed a rehabilitation program for alcohol use disorder. Dealing with the loss of her mother at a young age and a distant relationship with her father, she struggles to find a sense of belonging. She accepts a job renovating an apartment at the Dakota, eager to rebuild her career while investigating her family's historical connection to the building.

Theodore is a charismatic American architect overseeing the construction of the Dakota, a luxurious new apartment building in 1880s New York. Married to an English noblewoman, he moves through high society with ease but claims to value America's egalitarian ideals. He relies on his magnetic personality and professional ambition to establish himself in a rapidly growing city.

Melinda is a wealthy, entitled socialite living in a lavish apartment at the Dakota in the 1980s. She frequently refers to Bailey as her cousin, though they share no blood relation, and offers Bailey a job renovating her apartment. Accustomed to a life of privilege and excess, she embraces the decadence of the era, frequently partaking in drugs and alcohol while anticipating a large trust fund inheritance.

Minnie is the aristocratic English wife of Theodore Camden. As the daughter of a baron, she possesses the effortless confidence and refinement typical of the peerage. Often beset by illness, she relies heavily on staff to manage her household and children, projecting an intimidating presence to the working-class employees at the Dakota.

Daisy is a young, industrious maid hired to assist Sara with housekeeping duties at the Dakota in 1884. She is a romantic dreamer who openly wishes to ascend the social ladder by marrying a wealthy man. Despite her starry-eyed ambitions, she works exceptionally hard to support her impoverished family.

Mr. Douglas is the strict building manager of the Dakota. He views the staff, particularly female employees, with a critical and often condescending eye. He prioritizes the building's smooth operation and the avoidance of scandal over the personal well-being of his workers.

Renzo is the superintendent of the Dakota in the 1980s. Having grown up in the building, he knows its history and physical layout intimately. Initially gruff, he gradually becomes a supportive presence for Bailey as she investigates her family's past and works to maintain her sobriety.

Jack is Bailey's father, a mechanic living in New Jersey. Raised by a man who harbored a deep grudge against the Camden family, Jack adopted a cynical, austere lifestyle in direct opposition to the wealthy Camdens. Since his wife's passing, he has been emotionally withholding, leaving Bailey to navigate her struggles largely on her own.

Kenneth is an elderly resident of the Dakota who has lived there since the 1930s. He possesses a wealth of knowledge about the building's history and its eccentric, often treacherous social dynamics, offering Bailey a cynical but realistic perspective on the nature of the wealthy elite.

Tony is Melinda Camden's boyfriend in the 1980s. He matches her in decadence, frequently drinking and partaking in the city's nightlife. He encourages Bailey to join their revelry, seemingly indifferent to her recent completion of a rehabilitation program.

Tristan is the head of an interior design firm and Bailey's former boss. After she publicly insulted a client while intoxicated, he refuses to rehire her and becomes hostile when she secures the Dakota renovation job through Melinda instead of his firm.

Mrs. Haines is an assistant housekeeper at the Dakota. In contrast to the friendly Daisy, Mrs. Haines maintains a standoffish, strictly professional demeanor as she goes about her duties in the new luxury building.

Christopher is Bailey's grandfather. He was raised as a ward in the Camden household during the late nineteenth century but left at fifteen to join the Navy. Feeling rejected and financially abandoned by the family after Minnie Camden's death, he harbored a lifelong resentment that he passed down to his son, Jack.

Peggy is Bailey's late mother. Unlike her husband Jack, she attempted to maintain a connection with the wealthy Camden family, believing there had simply been a misunderstanding in the past. Her death left a profound void in Bailey's life, prompting her descent into substance abuse.