Rosie is an introverted true crime writer with a tendency to worry. She grew up in the Ozarks with con-artist parents who claimed to have supernatural powers, leaving her desperate to explain the world through rational facts. She recently inherited an apartment in the Windermere, a famous building where she experiences unsettling visions that challenge her logic.

Chad is an ambitious, extroverted actor who thrives on the attention of others. He is physically striking with a golden complexion and curly hair, currently working in an off-Broadway musical adaptation of Macbeth. He insists that he and Rosie move into the inherited apartment despite the building's dark history.

Willa is a resident of apartment 5B in the 1960s timeline. She is a dancer who longs for fame and the glittering nightlife of New York City, feeling trapped by the quiet domesticity her husband prefers. She harbors secrets and feels stifled by the expectations of marriage.

Ella is a wealthy, chic older woman who lives in apartment 5A at the Windermere with her husband. She possesses flawless style but carries worried eyes. Having lived in the building for decades, she maintains a close watch over the new arrivals and frequently offers gifts and hospitality to her neighbors.

Charles is the tall, soft-spoken eternal board president of the Windermere. Though in his seventies, he exercises daily and appears much younger. His family has deep roots in the building, and his grandmother was a famous medium who hosted seances in the very apartment he occupies.

Abi is the impeccably groomed doorman and elevator operator at the Windermere. He appears ageless and formal, acting as a romantic throwback to the city's past. He monitors the building closely through its high-tech intercom system and insists on maintaining strict order.

Max is a stylish publishing editor and Rosie's closest confidant. He is a self-proclaimed city nerd who loves obscure historical facts about New York architecture. He relies on facts and reality, providing a grounding influence when Rosie experiences anxiety.

Dana is a talented photographer with striking red hair and a raspy voice. She resents her late father for his past abuse and is furious that he left his valuable estate to her cousin Chad instead of her. She firmly believes Chad manipulated her father in his final days.

Paul is a quiet, introverted writer living in the Windermere in 1963. He prefers the safety of his sunny apartment over the chaotic nightlife of the city and hopes to start a family.

Sarah is Rosie's younger sister who still lives with their family in Tennessee. She possesses what their father calls the gift of dreaming, frequently having visions that predict trouble for her loved ones.

Ivan is Chad's late uncle and Dana's father. He recently passed away after a long illness, leaving behind a highly coveted apartment at the Windermere and a box of confusing documents.

Miles is the mischievous young son of Charles and Ella in the 1960s timeline. He discovers neighborhood secrets and uses them to threaten other residents.

Lillian is the adult daughter of Charles and Ella. She appears occasionally around the building and in photographs with other residents.

Dr. Black is Rosie's psychologist. He acts as a voice of scientific reason, repeatedly assuring Rosie that her terrifying visions are merely psychological manifestations of her past trauma.

Arthur is a historian specializing in New York architecture. He believes that buildings retain the memories of their inhabitants and provides Rosie with a theoretical framework for understanding the Windermere's hauntings.

Xavier is an anesthesiologist who lives in the Windermere. He appears nervous and unwilling to discuss the building's history while inside its walls.

Olivia is the stylish lawyer representing Rosie and Chad. She aggressively defends their interests and advises them on how to handle police inquiries.

Detective Crowe is a police investigator who questions the Lowans. He is skeptical of Chad's perfectly clean image and continuously presses Rosie for information regarding the deaths connected to her family.

George is a newer doorman who works at the Windermere. He interacts briefly with Rosie when she asks to see the building's security system.

Betty is a nurse who cared for Ivan Lowan during his final illness. She firmly believes Ivan intended for Dana to inherit the apartment.

Miranda is a medium who visits the Windermere. She accurately identifies Rosie's secret pregnancy and senses the presence of ghosts lingering in the building.

Anna is a sculptor who lives in the Windermere. She forms part of the strange and off-putting crowd of residents who greet Rosie upon her arrival.