Mack is a 30-year-old hotel manager who relocated to Nantucket 12 years ago after losing his parents in a car accident. He struggles with commitment and often feels torn between maintaining his family farm in Iowa and establishing permanent roots on the island. Avoidant of conflict, he attempts to juggle the expectations of his long-term girlfriend, Maribel, and the annual summer hotel guest, Andrea. He relies on older figures at the hotel to fill the parental void in his life.

Bill is the 60-year-old owner of the Nantucket Beach Club and Hotel, having inherited the business from his father. Recently diagnosed with angina, he struggles with depression and the pressure to retire. He desperately wants to keep the hotel in the family and expects his teenage daughter to eventually take over operations.

Therese is the 58-year-old wife of the hotel owner, characterized by her nurturing nature and a distinct white streak in her red hair. She uses her position to mother both the guests and the staff as a way to cope with the lingering grief of losing a stillborn son years earlier. She harbors strong opinions about who her daughter should marry to ensure the hotel's future.

Maribel is a librarian in her mid-twenties who has dated Mack Petersen for six years. Raised by a single mother, she acutely feels the absence of her father and seeks a stable, permanent home to soothe her insecurities. She grows increasingly frustrated by her boyfriend's refusal to commit to marriage or clarify their living situation.

Jem is a 23-year-old college graduate working at the hotel to avoid entering his father's bar business. Despite his good looks and past as a calendar model, he suffers from self-doubt and worries about disappointing his critical parents. He hopes to eventually move to California to work as an actor's agent.

Vance is a 30-year-old African American head bellman at the hotel. He carries a deep-seated grudge over a missed management interview 12 years prior, feeling constantly overshadowed by Mack. Beneath his anger, he is an intelligent, capable worker, a published writer, and a man searching for genuine connection.

Love is a 40-year-old front desk manager visiting from Aspen, Colorado. She accepts the summer job with a singular goal in mind: finding a suitable, unattached man to impregnate her before the season ends. She views biological motherhood as the solution to her loneliness and actively scouts the male guests for candidates.

Cecily is the 18-year-old daughter of the hotel owners. Smitten with a classmate from Brazil, she secretly plans to defer her college enrollment to travel abroad. She resents her parents' overprotective nature and their assumption that she will blindly take over the family business.

Lacey is an 88-year-old widow who has spent every summer at the beach club since 1945. She holds the distinction of being the oldest living Radcliffe College graduate. Deeply missing her deceased husband, she directs her unfulfilled maternal instincts toward the hotel staff, offering them candid advice.

Andrea is a single mother who returns to Nantucket every summer. She focuses most of her energy on raising her son and explicitly avoids serious romantic commitments. Her brief, seasonal interactions provide a convenient escape for those looking to avoid permanent decisions.

James is a 15-year-old boy who has autism. He visits the beach club with his mother every summer, bringing out a softer, more nurturing side in the hotel staff who step in to help teach him life skills.

Leo is a lawyer and regular guest attempting to manage a stressful family vacation. Recently left by his younger wife, he struggles to wrangle his two small children while trying to mend a tense relationship with his older sons from a previous marriage.

Arthur is a wealthy, charming, and married hotel guest. He enjoys flirting with the staff and projecting an air of entitlement, though his vague background raises immediate suspicions among the bell staff regarding the legality of his business dealings.

Known affectionately as "How-Baby," Howard is the president of the Texas Rangers baseball team. He takes a strong liking to the hotel management and offers career opportunities that force others to evaluate their long-term life plans.

Neil is a 42-year-old wealthy guest managing a severe cancer diagnosis. Rather than wallowing in his illness, he spends his vacation encouraging younger employees to seize opportunities, act on their feelings, and stop worrying about parental approval.

Jane is a recently retired custodian from a prestigious boarding school. She harbors a quiet sympathy for young romance due to her own unhappy life experiences, and she unexpectedly facilitates travel plans for the younger generation.

Gabriel is a Brazilian student who captures the heart of a recent boarding school graduate. His existence creates significant tension between his girlfriend and her parents, who view him with skepticism and dismissal.

Stephen is a man whose brief affair resulted in the birth of a daughter he never helped raise. His long absence has deeply affected his child, creating a lasting emotional void that influences her desperate search for stability and commitment in her adult relationships.

Cal is a nonchalant academic and annual guest at the beach club. He enjoys a peaceful, unattached lifestyle, offering a sharp contrast to the highly involved, anxious parenting styles of the hotel proprietors.