Brent is a 17-year-old high school junior who begins the story obsessed with material possessions, social status, and fitting in at his new Chicago private school. Following a disastrous party and a reckless decision that results in a fatal car crash, Brent receives a unique court sentence. He travels across the United States carrying a bus ticket and a woodworking manual, tasked with building four whirligigs as an act of restitution.

Lea is an 18-year-old high school senior, honor student, orchestra member, and active volunteer in the Filipino community. She is the innocent victim of the head-on collision caused by Brent. Her spirit and physical likeness become the inspiration for the wooden whirligigs built across the country.

Tamara is Lea's grieving mother. She seeks a meaningful form of restitution rather than financial compensation or a simple prison sentence. A philosophical woman interested in spirituality, she asks Brent to build four whirligigs in her daughter's likeness and place them in the four corners of the United States.

Steph is a highly logical 13-year-old girl living in Maine. Passionate about science and oceanography, she describes herself as puny and plain. She is initially skeptical of her best friend's belief in unseen forces until they take a walk to a wooden structure on a cliff.

Alexandra is Steph's confident best friend in Maine who believes in guided imagery and unseen forces. She leads Steph to a whirligig to perform a visualization exercise, hoping to help her friend attract romance.

Anthony is a fifth-grade boy from Seattle who was adopted from Korea as a baby. He loves baseball but faces intense pressure from his mother to excel academically and musically, causing him to resent his violin lessons.

Anthony's mother pushes him relentlessly to practice the violin and attend science camp. She uses a photograph of a harp-playing whirligig as a symbol to demand constant practice and perfection from her son.

He is a Puerto Rican street sweeper living in Florida. Having grown up during political upheaval and currently living in a crowded, noisy, multi-generational household, he deeply desires peace and quiet in his daily life.

Constancia is a waitress who marries the Miami narrator. She becomes overly anxious and loses her joyful demeanor after the tragic loss of their first baby, contributing to the stressful environment of their crowded home.

Jenny is a teenage girl in San Diego with a strong interest in her Jewish heritage and the history of the Holocaust. She goes on an emotional, nostalgic drive with her dying grandmother through the city.

She is an Auschwitz survivor suffering from terminal illness. She asks her granddaughter to drive her to places from her past, seeking to impart a final lesson about humanity and the presence of good in the world.

Emil is a German backpacker whom Brent meets at a youth hostel. Fluent in three languages and possessing a deep curiosity about history and science, Emil models an independent, intellectually rich life for Brent.

Chaz is a popular student at Brent's school in Chicago who hosts a human chess-themed party. He publicly humiliates Brent, treating him like a pawn and sparking a disastrous, angry reaction.

Brianna is a wealthy, popular girl at Brent's new school. When Brent tries to talk to her at the party to boost his own social standing, she loudly and publicly rejects him in front of their peers.

Jonathan is Brent's friend from his new school who accompanies him to Chaz's party. He forgets to mention the black-and-white dress code, causing Brent's initial embarrassment upon arrival.

He is a corporate employee whose recent promotion moves the family to Chicago. He remains stressed and unhappy despite increased affluence, sharing his son's preoccupation with appearances and material goods.

Brent's mother shares the family's focus on material possessions. She spends her time buying furniture and participating in a superficial family dynamic built around television commercials and wealth.

Miss Gill is the mediator assigned to handle the restitution meeting following the car crash. She guides the discussion and introduces the concept that actions have far-reaching, unknowable consequences.

She is a woman Brent meets on the beach in Maine while gathering materials for a woodworking project. She treats him with adult respect during their conversations and listens to his story.

He is a self-sufficient traveler touring the United States on a bicycle. He shares a Washington campsite with Brent, and they play the board game Go together while resting.