Magnolia is a Chinese American ten-year-old who spends her summer days observing customers at her parents' New York City laundromat. She amuses herself by building lint sculptures and maintaining a bulletin board of single socks left behind in the washers. Naturally observant and deeply creative, she struggles with loneliness until a new friendship inspires her to actively engage with the city around her.

Iris is a Vietnamese American girl adjusting to a difficult relocation from Santa Cruz to Manhattan. She initially complains about the crowds and smells of her new home but displays quiet bravery by launching a mission to return abandoned socks. She helps Magnolia build confidence while privately working to heal from her own turbulent family history.

Xiaohua is Magnolia's hardworking, practical mother who runs a busy Manhattan laundromat. She immigrated from China and adopted the English name Shirley in honor of the sweet, fizzy beverage. She works long hours to provide for her family, projecting a no-nonsense exterior that hides a whimsical past and a fierce, protective love for her daughter.

Aspen is a boy in Magnolia's grade who frequently insults the laundromat and behaves cruelly toward his classmates. He projects a tough, mean-spirited persona at school to deflect attention from his own fears and his father's harsh criticism. He holds a secret fondness for flamingoes, drawing inspiration from their unique ability to change color based on their diet.

Mr. Wu is Magnolia's father, a quiet and frugal man who helps operate the family business. Before living in the city, he supervised a large dahlia plantation, possessing deep knowledge about plants and their care. He demonstrates quiet acts of kindness toward the neighborhood children when they face emotional distress.

Ms. Lam is Iris's mother and a longtime friend of Xiaohua. She works at Salty Muscles gym and recently relocated her family from California to New York to build a safer life. She models resilience for her daughter by bravely standing up to neighborhood vandalism.

Alan is Magnolia's cousin who behaves seriously to please his strict parents. He practices piano and studies constantly, leading Magnolia to view him as boring and condescending. Underneath his studious exterior, he harbors a deep passion for fashion design and knitting.

Auntie Mei is Xiaohua's sister and Magnolia's aunt. She places high academic and behavioral expectations on her son, creating a tense atmosphere during family gatherings. She praises Magnolia's independent exploration of the city.

Luis is a boy from Magnolia's school who helps out at his father's barbershop, HAIR. He trains under his father's guidance and values the stories his customers share while sitting in the barber chair. He possesses a sentimental attachment to a particular black-and-white checkered sock.

Mr. Mateo is a local barber who operates a shop featuring distinctive black-and-white checkered floors. He teaches his son that listening to people's stories is a vital, rewarding part of their profession.

Jessica is a lonely girl whose mother owns a large ice cream company. Despite living in an expensive, quiet building with a nanny and a doorman, she envies Magnolia's busy, community-oriented life at the laundromat. She eagerly joins the sock-returning squad to escape her isolation.

Sunny is Jessica's nanny. She oversees the girl in her quiet, pristine apartment while Jessica's mother is away working on television commercials.

Carl is a local chess player who frequents the city park. He offers Magnolia and Iris early advice on their quest, encouraging them to enjoy small victories rather than worrying about mistakes.

Lisa is a laundromat customer who loves crossword puzzles and works in the subway system. She boosts Magnolia's confidence by praising the young girl's creative thinking when she makes a spelling mistake.

Levi owns a local diner that Magnolia frequently visits. He knits his own orange and black coasters for the restaurant, prompting the girls to investigate him for a missing pink sock.

Rosa runs a local plant shop and maintains a "plant hospital" for uprooted greenery. She shares stories with Magnolia about Mr. Wu's impressive agricultural past, expanding the girl's understanding of her own father.

Zito is a friendly pizzeria owner who praises the Wu family's laundry services. He takes the time to learn the correct pronunciation of Xiaohua's given name and firmly defends Magnolia from local bullies.

Mr. Yoon is a doorman who retrieves Magnolia's forgotten knapsack. He shares personal wisdom about the inevitability of change and the importance of holding onto valuable friendships during times of conflict.

Ali runs a neighborhood bodega filled with coconut-scented products. He patiently helps the girls smell different items to match a mysterious sock, showcasing the community's willingness to help.

Mr. Ishioka is the school custodian, originally from Japan. He brings joy to his work by gracefully sliding across the freshly sprayed floors in his socks, turning a mundane chore into a beautiful figure-skating routine.

Mr. Pants is the Wu family's pet dog. His friendly, welcoming nature helps break the ice when Iris first visits the busy laundromat.

Pockets is the resident cat at Ali's bodega. Her mischievous habit of stealing items unexpectedly helps the children uncover a hidden clue on a wet sock.