Ruth is a 28-year-old waitress enduring the grueling seasonal economy of Block Island. Having lost her mother to cancer a decade ago, she remains stuck in a cycle of temporary jobs and emotional avoidance. She relies heavily on her connection to the late photographer Diana Beckett, who served as her mentor. She struggles with financial precarity and a deep sense of aimlessness.

Charlie is Diana's nephew and a frequent summer visitor to Block Island. He holds a long, emotionally undefined connection with Ruth that began during their teenage years. Now based in Boston, he is engaged to Nadia, creating tension between his stable present and his unresolved past on the island.

Diana is a successful photographer who left the New York fashion world for a quieter life on Block Island. She acts as a surrogate mother to Ruth, offering her sanctuary and encouraging her to write. Her sudden death from lung cancer leaves a massive void and a complex legacy for those she left behind.

Louis is a local fisherman and an old acquaintance of Ruth's on Block Island. He shares a casual romantic history with her, fitting comfortably into her transient summer routine. He is maturing out of the seasonal lifestyle and working toward purchasing his own fishing business.

Lucy is Ruth's best friend and roommate. She is an ambitious young woman actively pursuing her career goals, making her a direct opposite to Ruth's stagnation. She frequently pushes Ruth to confront difficult truths about her life choices.

Joel is Ruth's emotionally distant father and a painter. Overwhelmed by his own grief following his wife's passing, he sent his teenage daughter away, creating a long-standing rift between them. He struggles to communicate his feelings effectively as his health declines.

Maggie is Ruth's late mother. Remembered as a practical teacher and devoted parent, her death plunged her daughter into a decade of aimless grief. She harbors a hidden past connected to Block Island that slowly comes to light after Diana's death.

Lynn is Diana's sister and Charlie's mother. She enforces the strict social boundaries of Block Island's wealthy elite. Following Diana's death, she takes control of the estate and actively tries to exclude Ruth from her family's affairs.

Nadia is a successful, charitable artist engaged to Charlie. She represents the conventional, forward-moving life Charlie has built away from Block Island. Her presence forces Ruth to confront the reality of Charlie's commitments.

Bonnie is a local librarian on Block Island. She assists Ruth when she first arrives on the island with a broken phone and a smudged address.

Ethel is an editor at Vogue magazine. Acting on Diana's request, she contacts Ruth with a tight deadline to write a major profile on the late photographer's life.

Peter is a friend of Charlie's from college. He attends social gatherings on the island, reinforcing Charlie's ties to his affluent Boston life.

Ellen is a college friend of Charlie's. She originally introduced him to Nadia and views them as a perfect match.

Whitney is Ruth's boss at the Block Island restaurant. She deals with the pressures of the seasonal service industry and manages Ruth's unpredictable behavior.

Marilynne is Diana Beckett's lawyer. She is responsible for executing the late photographer's will and contacting beneficiaries with unexpected news.