Henry is an American expatriate and aspiring writer living in Paris. He endures extreme poverty and frequent starvation but remains devoted to producing a new, unconventional style of literature. Rejecting established moral codes and intellectual systems, he prefers to immerse himself fully in the sensory world. His days consist of wandering the city, philosophizing, and seeking out basic sustenance while reflecting on his memories.

Fillmore works in the diplomatic service and comes from a wealthy American family. He frequently distributes money to his impoverished artist friends, lacking their literary sophistication but offering crucial financial support. Despite his social and financial advantages, he exhibits severe helplessness when managing romantic encounters and emotional crises.

Van Norden works alongside Henry at the newspaper and attempts to write a novel, though his desire for absolute perfection paralyzes his progress. He maintains a profoundly pessimistic outlook on life, waking up daily to curse his existence and the city around him. He expresses aggressive misogyny toward women while secretly harboring a deep, consuming fear of loneliness.

Mona is Henry's estranged wife who remains physically absent in America for most of the narrative. She occupies a powerful psychological space in Henry's mind, coloring his geographic memories of the city. Her emotional influence disrupts his present relationships and dictates his darkest psychological torments.

Tania is a passionate Jewish woman living in Paris who engages in an intense affair with Henry. She serves as a primary inspiration for his writing, taking on a nearly mythic status in his creative imagination. She displays fierce jealousy when Henry directs his attention toward other women or even his meals.

Boris shares the squalid Villa Borghese apartment with Henry at the start of the novel. He participates in Henry's grandiose plans to invent a new literary mythology. He endures the same poverty as Henry and periodically vanishes from the city.

Carl is an expatriate writer who despises the characteristic optimism of his fellow Americans. He frequently concocts manipulative schemes to infiltrate the local literary scene, though he rarely executes them. He maintains an ongoing correspondence with a wealthy, older woman named Irene.

Sylvester is Tania's husband and a hospitable friend to Henry. He eagerly supports Henry's writing process, seemingly unaware of the intense dynamic occurring between Henry and Tania.

Moldorf is a verbose associate of Henry who possesses a deep passion for literature but struggles to write successfully himself. He fixates intensely on Tania because she bears a resemblance to his absent wife.

Kruger operates as a spiritual-minded sculptor and painter in Paris. He produces mediocre art but maintains a wide social circle of expatriates. He provides Henry with temporary shelter and introduces him to several key associates.

Mark Swift is an Irish painter living in Paris. He produces uninspired art while aggressively mistreating his unnamed mistress, who possesses far more artistic talent than he does.

Collins is an American sailor who drinks heavily and tells engaging stories of his travels down the Yangtze River. He later hosts Henry and Fillmore when they visit the port city of Le Havre.

Macha is an erratic woman who claims to be an exiled Russian princess working on a movie shoot. She creates chaos in the apartment with her poor health, frequent arguments, and relentless demands for attention.

Ginette is an aggressive, manipulative Frenchwoman. She uses claims of pregnancy to try to force Fillmore into marrying her, displaying volatile and abusive behavior when he attempts to establish independence.

Serge is a large, imposing Russian man and a former captain in the Imperial Guard. Despite his size, he is extremely gentle and hires Henry as an English teacher, though his living conditions are exceptionally dirty.

Nanantatee is an Indian pearl merchant operating in Paris. He provides Henry with shelter but frequently behaves in a controlling and condescending manner toward him.

Peckover works as a proofreader at the same newspaper where Henry's friends are employed. He saves his meager earnings in a desperate attempt to buy a set of false teeth.

Marlowe is an American aspiring writer struggling to survive in Paris. He runs a literary magazine that he attempts to hand off to Henry and Carl when he considers returning to San Francisco.

Germaine is a Parisian sex worker whom Henry remembers fondly. She values her body highly, treating her anatomy as a potent treasure, which deeply impacts Henry's philosophical views on sex.

Claude operates as a sex worker in Paris who approaches her profession with a profound sense of sadness and reluctance. Her delicate, shy demeanor ultimately frustrates Henry.