Max is a middle-aged art historian who travels to the seaside following the death of his wife, Anna. He rents a room at the Cedars, a guesthouse that once served as a grand holiday villa during his youth. Instead of working on his planned monograph about the painter Bonnard, he drinks heavily and fixates on his childhood memories. He remains highly insecure about his lower-middle-class background, relying on an unreliable, heavily idealized version of his past to cope with his present grief.

Anna is Max's recently deceased wife, a woman from a wealthy background whose father earned his fortune through morally ambiguous business dealings. During her life, she works as an assertive photographer, creating portraits that often leave Max feeling uncomfortable and exposed. When hospitalized for cancer, she turns her camera on the other patients to document their physical vulnerabilities.

Connie is the elegant mother of the Grace family, renting the Cedars during Max's youth. She arrives with an air of cosmopolitan sophistication that stands in sharp contrast to Max's own modest background. To the young, socially insecure Max, she appears almost mythological, becoming the focus of his intense, idealized adolescent curiosity.

Carlo is the patriarch of the wealthy Grace family. He presents a robust, confident physical presence, typically dressed in khaki shorts. For young Max, Carlo embodies an intimidating, animalistic masculine energy that simultaneously provokes fear and deep-seated envy.

Chloe is the wealthy, confident daughter of the Grace family. As a pre-teen on summer holiday, she acts with a strong sense of entitlement and frequently displays a cruel streak. She commands the attention of young Max, drawing him away from his usual friends and pulling him into her volatile, boundary-testing games.

Myles is Chloe's nonverbal twin brother. Distinguished by his webbed toes, he is a strange, silent boy who follows his sister everywhere. He communicates with Chloe through a near-symbiotic link and enthusiastically participates in her mischievous, sometimes malicious activities.

Rose is a young woman employed as a governess for the Grace family. She accompanies them on their summer holiday at the Cedars. As a servant, she lacks the aristocratic glamour of her employers and frequently endures mockery and physical torment from her young charges, Chloe and Myles.

Claire is Max and Anna's adult daughter. Following her mother's death, she travels to Ballyless to check on her father, deeply concerned by his heavy drinking and erratic behavior. She attempts to bring order to his life by arranging for him to move in with her, despite his stubborn resistance and dismissal of her own grief.

Colonel Blunden is a fellow paying guest staying at the Cedars during Max's return visit. He presents himself as a bluff, cheerful ex-military man with a rigid daily routine. Max views him with intense suspicion, doubting his military background and silently mocking his friendly overtures.

Vivienne is a wealthy, condescending woman who visits the guesthouse. She treats Max's bereavement with a pitying attitude that irritates him, and her patrician demeanor exposes Max's lingering insecurities about his own social class. Her presence introduces a tense, unspoken power dynamic into the house.

Max's mother is a woman who struggles to maintain her family's dignity while staying in a modest tarpaper chalet. She is acutely aware of the class divide at the seaside resort and becomes increasingly bitter about Max's desperate attempts to ingratiate himself with the wealthy Grace family. After her husband abandons them, she faces severe financial hardship.

Max's father is a man who brings his family to a modest holiday chalet before eventually leaving them for a new life in England. Before his departure, he behaves with a rough, mock-playful physicality that sometimes embarrasses his son. His ultimate abandonment forces his wife into financial struggle and leaves young Max with a profound sense of social shame.

Mr. Todd is the medical professional who treats Anna. He delivers the grim news of her terminal cancer diagnosis, a moment that abruptly shifts the course of Max and Anna's lives. Max finds his name darkly amusing due to its phonetic similarity to the murderous barber Sweeney Todd.

Jerome is Claire's fiancé. He accompanies Claire to retrieve Max from the seaside village, quietly supporting her as she manages her difficult, grieving father. Max harbors a general disapproval of him, which strains family dynamics.

Anna's father is a wealthy businessman. He amasses a fortune through morally dubious activities, leaving behind an inheritance that significantly elevates Max's financial status. Anna notes that her baldness during chemotherapy makes her strongly resemble him.

The townie boy is a local child of a modest social background. He becomes a target of Chloe's bullying, an incident that forces Max to confront his own social shame by choosing not to intervene.

The hospital patients are individuals sharing Anna's ward during her final illness. They become the subjects of Anna's final photography project, which highlights their physical deformations and ailments.