Daphne is a 53-year-old English teacher at a girls' prep school who lives in Bronxville, New York. She maintains a carefully ordered life that is suddenly disrupted when she unexpectedly reunites with her former stepfather, Eddie, after 44 years. As a child, she survived a traumatic car accident while riding with Eddie, an event that deeply influenced her family's history. She relies heavily on books to process the world and carries unresolved feelings regarding her childhood.

Eddie is a 76-year-old book editor still working at Random House in New York City. Decades earlier, he was married to Daphne's mother, serving as a warm and stabilizing figure in Daphne and Leda's young lives before a sudden separation severed his ties with the family. He possesses a deep affection for literature and views his editorial career as a way to stay close to the writing process.

Jonathan is a 70-year-old retired hospital administrator who lives a quiet, organized life with Daphne in Bronxville. Having lost his first wife to cancer, he possesses a quiet empathy for grief and loss. He is highly observant of his surroundings and actively supports Daphne as she begins to process the sudden reappearance of her former stepfather.

Abigail is Daphne and Leda's mother, a pragmatic woman living in Winchester, Massachusetts. Her decisions have shaped the central conflicts of her family, particularly her choice to completely banish Eddie following a traumatic car accident. She demands control over her environment and prioritizes stability, leading her to marry three vastly different men over the course of her life.

Leda is Daphne's younger sister and works as a clinical psychologist who writes a column for the New York Times. She approaches difficult situations with analytical thinking and a practical sense of empathy. Like Daphne, she carries long-held childhood assumptions about their family's past, particularly regarding an illness she suffered as a young girl.

Skip is a retired senior partner at a law firm and Eddie's former college roommate from Yale. He leads a highly public, conventional life as a successful lawyer and family man. Despite his polished exterior, he can be abrasive and openly critical, maintaining a complex, decades-long dynamic with Eddie that he guards closely from outsiders.

Polly is Skip's wife, deeply involved in organizing the social obligations of her family circle. She values tradition and carefully manages the appearances of her relationships. She considers Eddie to be a core part of her family network and closely monitors his well-being, often demonstrating high anxiety regarding his health.

Buddy is Daphne and Leda's biological father, a man who preferred the life of a fisherman over the responsibilities of domesticity. His devotion to the ocean created physical and emotional distance from his daughters. Despite his absence, he left behind practical items, like a well-stocked emergency kit in an old car, that inadvertently protected his family later on.

Lucas is Abigail's current husband, an author who built a publishing empire on positivity and self-help principles. He provides the Ekker household with significant financial stability, allowing the family to live comfortably in Winchester. He can be somewhat self-absorbed and demanding, maintaining an emotional distance from his stepdaughters.

Henry is Leda's 17-year-old son. Unburdened by the historical emotional baggage of his mother and aunt, he views the family dynamics with clear-eyed detachment. He observes the adults around him directly and states his thoughts without hesitation, providing an outsider's clarity to long-standing family mysteries.

Candy is Jonathan's late first wife. Though deceased, her presence remains in the Fuller household through her curated collection of rabbit paintings. Her battle with cancer and unfulfilled travel dreams continue to inform Jonathan's decisions and his protective instincts toward Daphne.

Matthew is Daphne and Leda's younger half-brother from their mother's third marriage. He grows up in the stable, affluent environment provided by Lucas's success. His personal journey during college eventually challenges Abigail to show a compassion she struggled to provide in her earlier marriages.

Christopher is Daphne and Leda's half-brother, born to Abigail and Lucas. He is raised in the suburban comfort of Winchester and remains close to his parents, helping to manage family affairs.