Douglas Spaulding
Douglas Spaulding is the young protagonist of the novel. Full of spirit and empathy, he becomes the lens through which the particular summer is seen. He is an intuitive observer of the world around him and feels things very deeply. By the end of the summer, due to the piling up of deaths and uncomfortable changes, he wonders if he wants to continue living but eventually decides he will.
Tom Spaulding
Tom Spaulding is the free-spirited younger brother of Douglas. While Douglas is innocent, Tom is more logical and skeptical. He relentlessly questions the actions of his brother. He is not easy to convince and his revelations are more profound.
Charlie
Charlie is a friend of Douglas and Tom and frequently spends time with them. Charlie has a minor role to play in the novel.
Leo Auffmann
Leo is Tom and Douglas's neighbor. Leo initially suggested that Tom and Douglas not talk about miserable subjects, and was then counter-suggested to make a Happiness Machine. He successfully creates the machine but it nearly destroys his family, and he comes to realize that his family and their life together is happiness.
Dad
Douglas and Tom's father, he is friendly and loving and enjoys spending time with his children. He takes his sons out to the forest at the beginning of summer, which turns out to be a rite of passage for Douglas.
Mother
A calm and loving mother to Douglas and Tom, Mother embodies aspects of traditional early 20th-century womanhood (i.e., she is mostly known as a wife and mother) but she is also intelligent and rational.
Grandfather
The kindly grandfather to Douglas and Tom, his summer begins when the grass is long enough to be cut; he loves the act of mowing the lawn because it is contemplative.
Grandma
Douglas and Tom's loving and hardworking grandma, she is an excellent cook but only in her way - with intuition, a messy kitchen, and spontaneity. Aunt Rose almost messes this up forever but the family steps in to get rid of the visitor and have things go back to the way they ought to be.
Great-Grandma
The tireless and warm matriarch of the family who decides near the end of the summer that her clock has wound down and it is time to die. Over her family's protestations she explains that she is old and has lived her life and wants to go while she's still entertained.
John Huff
A kind, charismatic friend of Douglas, he has to suddenly move away because his father gets a new job. This is very hard on Douglas.
Mr. Sanderson
He is the kind and elderly proprietor of the shoe store from where Douglas decides he must have new summer sneakers. At Douglas's bequest, he tries on the wonderful shoes and experiences feelings of swiftness and wildness. He allows Douglas to work off money that he owes for them by performing odd jobs.
Lena Auffmann
Lena is Leo's long-suffering wife who tells him they do not need a Happiness Machine because they are already happy. Leo's obsession bothers her and she almost leaves him. She tries out the machine herself and is depressed by all the fake things she sees inside.
Bill Forrester
A neighbor of Grandfather and Grandma and a local newspaperman, he is about thirty and is unmarried. He begins to develop a crush on the elderly Helen Loomis when he sees a picture of her when she was young. The two become intimate friends and he mourns her death, wishing that they had met when they were the same age.
Mrs. Bentley
She is an elderly woman who just recently moved to the town; her husband died years ago. Tom and his girlfriends do not believe she was ever young, and eventually she realizes it is better to live in the present than the past so she agrees with them that she has always been old.
Colonel Freeleigh
He is an elderly man nicknamed "The Time Machine" because he has wonderful, detailed stories of the past that he loves to share with the children. He is very ill, however, and is not supposed to do things that excite him. He enjoys calling a friend in Mexico City so he can hear the sounds of a place he once loved, but this brings about his death.
Miss Fern and Miss Roberta
They are two elderly women in the town who purchase the Green Machine but accidentally strike someone with it and then hide it away.
Mr. Tridden
The trolley motorman, he gives the children one last ride and a picnic because the bus is replacing the trolley and he is going to retire with a nice pension.
Elmira Brown
A townswoman married to postman Sam Brown, she is convinced that the leader of the Honeysuckle Ladies Club, Clara Goodwater, is a witch and out to get her. She confronts the ladies with this information and tries to make them vote for her for president, but Clara uses her magic on her. She falls down a staircase and almost dies, but Clara and her friends are distressed and promise to be good to her now.
Clara Goodwater
She is a townswoman who turns out to be a witch; this comes to light after Elmira Brown believes she has found enough information to denounce her and prevent her reelection as president of their shared club. After Elmira almost dies, Clara is extremely regretful and apologetic, and it is suggested that they become friends.
Helen Loomis
An elderly woman who lives in the town, she was once very beautiful but never married; instead, she devoted her life to traveling. She meets young Bill Forrester and spends the last few weeks of her life with him, regaling him with stories of her past and dreaming about if they'd only met when they were the same age.
Lavinia Nebbs
An unmarried 33-year-old woman known for her beauty and intelligence, Lavinia is not afraid of the Lonely One even though others in the town are. She insists on living her life and going to the movies and drugstore even after she and a friend stumble across the body of a missing woman in the ravine. Her friends suggest she might even want to die and is too bold, but she insistently dismisses them and walks home alone through the ravine. Eventually she fears she is being followed so she runs as fast as she can; however, the attacker is inside her house and she stabs him with scissors.
Francine
A young woman and a friend of Lavinia's, she and Lavinia discover the missing woman's body on their way to the movies. Francine experiences much emotional distress due to this. She has a bad feeling about Lavinia walking home alone but cannot dissuade her friend from doing so.
Helen Greer
She is a young woman and friend of Lavinia and Francine.
The Tarot Witch
An arcade game, the Tarot Witch is an enigmatic figure whom Douglas is convinced is a real woman trapped under wax and whom must be freed from the grasp of Mr. Black.
Mr. Black
He is the angry and irritable proprietor of the arcade who tries to destroy the Tarot Witch when he is annoyed that she does not predict success for him.
Mr. Jonas
An itinerant junkman who travels from town to town, he gives people the opportunity to find things they like and get rid of old things they do not. He essentially saves the sick and depressed Douglas's life by offering him precious bottles of fresh, revivifying air.
Aunt Rose
She is a family member who comes to stay with the Spauldings, but quickly wears out her welcome when she pushily starts to change the way Grandma organizes her kitchen and cooks. She is unceremoniously asked to leave.