Grace is an unemployed woman who casts herself as an interior designer. She is hyper-focused on maintaining social appearances and gaining influence among her peers. She actively favors her older daughter over her younger one and takes pride in her new luxury apartment at Sunset Towers, viewing it as a status symbol.

Turtle is the independent-minded younger daughter of the Wexler family. She wears her hair in a long braid and aggressively kicks the shins of anyone who pulls it. Feeling neglected by her mother, she focuses her sharp intelligence on the stock market and treats the inheritance game as a financial investment.

Angela is the beautiful and obedient older daughter of the Wexler family. She is engaged to a young medical intern but feels stifled by the expectations placed upon her. Neighbors frequently treat her as a delicate object rather than an independent person with her own ambitions.

Judge Ford is a highly educated and independent judge with a complicated history tied to the Westing family. She approaches the mystery with methodical research, seeking a logical explanation for the strange events surrounding the inheritance. She suspects the game is a trap meant to punish a specific individual.

Crow is a severely dressed cleaning woman who wears all black and has exceptionally pale skin. She is deeply religious, frequently citing sin and demanding repentance from those around her. She works at Sunset Towers and volunteers her time at a downtown soup kitchen.

Samuel Westing is a wealthy paper magnate and the orchestrator of the inheritance game. His bizarre will dictates that one of his sixteen potential heirs took his life. As the mystery unfolds, the residents interact with his various associates and aliases, including the cheerful doorman Sandy McSouthers, who guards Sunset Towers, and the elusive Barney Northrup, who initially rented them their apartments.

Jake is a podiatrist who runs his medical practice out of his apartment suite in Sunset Towers. He maintains a somewhat distant relationship with his wife early on and harbors a secret career as a bookie. He sits out the initial reading of the will but joins the mystery as the game progresses.

Denton is an intern at the local hospital studying to become a doctor. He is engaged to the beautiful Angela Wexler and initially appears highly focused on his medical career. He views the inheritance game mostly as an inconvenience but stays involved to secure his portion of the money.

Mr. Hoo owns and operates Shin Hoo's Restaurant on the top floor of Sunset Towers. He struggles with a painful ulcer and holds a bitter grudge against Samuel Westing over a disputed disposable paper diaper invention. He is a demanding father who constantly pressures his son to study instead of running track.

Madame Hoo is a Chinese immigrant who speaks very little English. She often feels isolated and lonely in Sunset Towers, gazing out the window and longing for her home country. Her husband requires her to wear a fitted dress with a thigh-high slit to serve as a hostess in their restaurant.

Doug is a high school student and a talented track star. He constantly jogs in place or runs to practice, much to the frustration of his father. His athletic speed proves useful for keeping tabs on other residents and acting as a lookout during various building antics.

Sydelle is an ignored secretary who desperately craves attention from those around her. She moves into a rear-facing apartment in Sunset Towers and buys a pair of wooden crutches, painting them to match her outfits in a bid to make people notice her. She holds an advantage in the game by taking shorthand notes during the reading of the will.

Otis is a 62-year-old delivery man who frequently yells to startle the residents. He distributes the letters to the tenants and enjoys spreading frightening rumors about Samuel Westing's corpse among the younger building occupants.

Flora is a timid, exceedingly polite dressmaker who works out of her apartment. She previously owned a bridal shop and harbors private grief over the loss of her daughter, Rosalie. She readily follows her game partner's aggressive financial strategies, finding comfort in the companionship.

Chris is a 15-year-old boy who uses a wheelchair due to a condition that causes muscle spasms and stuttering. He is highly observant and spends his days birdwatching from his window, allowing him to track the secret movements of his neighbors. He takes pride in noticing things that others miss.

Theo is a high school student who works in his parents' coffee shop on the ground floor of the building. He dreams of becoming a writer but plans to delay his education to help care for his brother. He is protective of his family and highly competitive in the mystery.

George runs the coffee shop on the ground floor of Sunset Towers. He is a hardworking father who provides for his family and stays largely out of the inheritance game drama, though his past connection to the Westing family draws the judge's suspicion.

Mrs. Theodorakis operates the ground-floor coffee shop alongside her husband. She is a dedicated mother who finds herself terrified when a bomb goes off in her kitchen, completely destroying her workspace.

E. J. Plum is the young attorney tasked with reading Samuel Westing's will. He administrates the game, distributes the checks, and hands out the clues to the heirs, often seeming just as confused by the proceedings as they are.

Violet is Samuel Westing's deceased daughter. Though she died years before the events of the story, the tragic circumstances of her death cast a long shadow over the older residents of Sunset Towers, serving as a key piece of the historical puzzle.