Harry is a Jewish New Yorker in his early twenties who spends his days seeking his next heroin fix alongside his best friend, Tyrone. He frequently steals from his lonely mother to pawn her belongings for cash. Despite his severe addiction, he harbors idealistic plans of becoming a successful drug dealer and eventually opening a community art café with his girlfriend.

Sara is a widow living a deeply isolated life in Brooklyn. She spends most of her time watching television and eating chocolates, using daytime media as a surrogate for human companionship. When she receives a phone call suggesting she might appear on a television broadcast, she becomes obsessed with losing weight to fit into a special red dress. She eventually turns to prescription diet pills to accelerate her physical transformation.

Tyrone is a young Black man surviving the rough streets of New York alongside his best friend, Harry. Having lost his mother at a young age, Tyrone longs for a comfortable life free of daily stress. He provides the crucial connections to the local drug network that allow him and Harry to buy and sell heroin. He frequently faces racial profiling and prejudice from law enforcement that his white peers do not experience.

Marion is a cultured young woman from an upstate middle-class family who financially supports her life in the city. She loves classical music and dreams of opening a European-style bohemian café. Despite her refined tastes and financial safety net, her growing dependence on heroin begins to overshadow her artistic aspirations. Her need for drug money eventually leads her to blur professional lines with her therapist and compromise her personal boundaries.

Arnold is Marion's psychiatrist. He takes her on expensive dates to French restaurants, fundamentally crossing the boundaries of a healthy doctor-patient relationship. He provides Marion with cash from her parents' therapy stipends, money she quietly funnels into her drug habits.

Brody is a local drug supplier connected to the New York heroin scene. He serves as Tyrone's primary contact for purchasing strong batches of heroin that Harry and Tyrone plan to cut and sell for profit.

Mr. Rabinowitz is an elderly neighborhood pawn shop owner. He knowingly accepts Sara's television when Harry steals it for drug money, keeping a specific ledger just for these recurring transactions. He reliably sells the television back to Sara for a small markup shortly after.

Ada is Sara's friend and neighbor in her apartment building. She actively participates in the excitement surrounding Sara's television invitation and frequently joins her to wait for the mailman.

Lyle Russell is a representative from the McDick Corporation. He makes the fateful phone call informing Sara that she has been selected to appear on a quiz show, an event that single-handedly alters her life trajectory.

Seymour is Sara's deceased husband and Harry's late father. He exists purely in Sara's memories of happier times before Harry's addiction consumed their lives.

Alice is Tyrone's girlfriend. She enjoys the material comforts and steady drug supply that Tyrone briefly provides when his business partnership with Harry takes off.

Rae is another of Sara's neighborhood friends. She checks in on Sara's wellbeing and witnesses the physical toll of her intense, pill-fueled dieting regimen.

Angel works at the local city morgue. He uses his grim workplace as a private gathering spot, allowing Harry, Tyrone, and their wider social circle to party and inject heroin away from public scrutiny.

Gogit is a neighborhood street dealer. He supplies heroin to Harry, Marion, and their friends during their social gatherings.