Patrick is a nearly 50-year-old actor experiencing a career resurgence while secretly dealing with personal insecurities. Five years ago, he took in his niece and nephew during a family crisis, forming a permanent bond with them. Now, he faces anxiety about aging and his recent breakup with his younger boyfriend, Emory. He acts as a guide to his niece and nephew, bringing them across Europe in an attempt to teach them about love and family acceptance.

Maisie is Patrick's 14-year-old niece. Entering her teenage years, she is angsty and fiercely protective of her late mother's memory. She actively resists her father's upcoming marriage, fearing that a new stepmother will erase the family she remembers. She pushes boundaries and tests Patrick's authority as she manages her evolving identity.

Grant is Patrick's 11-year-old nephew. Having lost his mother when he was only six, his memories of her are fuzzier than his older sister's. He often follows Maisie's lead in their unified front against their father's new relationship, though he also harbors a quieter desire for a maternal figure in his daily life.

Greg is a lawyer, Patrick's brother, and the father of Maisie and Grant. Five years after losing his wife and completing rehab, he has found happiness again and is eager to start a new chapter. Though confident in his love, he struggles to bridge the gap between his own desires and his children's grief-fueled resistance to his remarriage.

Palmina is Livia's younger sister, an independently wealthy, effortlessly cool Italian lesbian. Dubbed a "launt" (lesbian aunt) by the kids, she dresses androgynously and carries a confident, worldly aura. She quickly becomes a role model for Maisie, providing the kind of modern female perspective that Patrick struggles to offer.

Livia is Greg's fiancée, hailing from a wealthy aristocratic Italian family. Having struggled to have children of her own, she is eager to become a mother figure to Maisie and Grant. Despite the children's coldness toward her, she remains patient, hoping to earn their trust without erasing the memory of their late mother.

Clara is Patrick and Greg's older sister. Previously rigid and critical of Patrick's caretaking skills, she is now recently divorced, through menopause, and enjoying a lighter, more carefree phase of life. She serves as a supportive sidekick to Patrick in managing the children and family drama during the wedding festivities.

Emory is Patrick's younger ex-partner of five years. Patient and devoted, he never saw their nearly 15-year age difference as an issue, even though Patrick's anxieties caused their recent split. He provides grounding energy in Patrick's life, showing unwavering commitment despite Patrick's tendency to overthink their relationship dynamics.

Cassie is Patrick's dedicated talent agent. Ambitious and protective of his career resurgence, she flies across the world to push him toward new roles, including a potential Broadway revival of Grease. She often acts as a sounding board for Patrick's professional and personal anxieties.

Sara is Greg's late wife, Patrick's former college best friend, and the mother of Maisie and Grant. Though she died five years prior to the events of the novel, her memory heavily dictates the actions of her family. She was vibrant, practical, and deeply loving, leaving a lasting impact that the family is still learning to process.

Joe is Patrick's late partner, whose tragic death years ago sent Patrick into a long period of isolation in Palm Springs. Although not present in the current timeline, his loss fundamentally shaped Patrick's understanding of grief, love, and the difficulty of moving forward.

Gustavo is an older man who Clara meets and connects with in Italy. With limited English, he primarily communicates by introducing himself, serving as a lighthearted companion for Clara during her post-divorce exploration.

Pip is a hotel clerk at Patrick's accommodations in London. Helpful and attentive, he assists Patrick after a long day on set, representing the fleeting interactions in Patrick's transient actor lifestyle.