Carol is a 12-year-old girl who anglicizes her birth name, Carolina, to fit in with her peers at middle school. She is initially unhappy about spending her summer on her grandfather's arid sheep ranch instead of socializing in the city. Struggling with insecurity about her appearance and Mexican American heritage, she feels completely out of place in the desert. Over the course of the summer, she becomes captivated by the environment and her grandfather's stories.

Serge is an elderly sheep rancher proudly clinging to his Mexican roots and his property. He suffers from dementia, which causes him to experience emotional outbursts, confusion, and memory loss. He strongly resists his family's plans to move him to an assisted living facility called The Seville. Instead of cooperating with the transition, he shares elaborate, magical stories about the history of the ranch with his granddaughter.

Raúl is Carol's father and a professional contractor who returns to his childhood home to clean it up for sale. He left the ranch at age 17 and harbors long-standing resentment toward his father and the desert environment. The stress of managing the physical labor on the property, his father's declining health, and difficult family dynamics pushes his patience to its absolute limit.

Patricia is Carol's mother and a nurse who commutes from the ranch back to the city for night shifts. She takes charge of organizing the family's meals and daily tasks while managing the stressful situation of her father-in-law's declining health. She actively attempts to maintain a connection to their heritage by cooking spicy Mexican meals, a deliberate change from the boxed dinners the family usually eats at home.

Alta is Carol's 17-year-old half-sister. She arrives at the property in a car purchased by her biological father, immediately causing friction with her mother. She exhibits moody behavior and frequently attempts to avoid the hard labor required to clean up the ranch. Her attitude oscillates between acting sweet toward Carol and acting entirely cold, largely stemming from feeling disconnected from the core family unit.

Rosa is Carol's deceased grandmother. She serves as a central figure in Serge's stories, depicted as a brave young woman in an enchanted village who desires to leave safety behind to travel the world. Serge and Raúl frequently comment on Carol's physical resemblance to Rosa, noting that the two share the same spirited, fiery personality.

Lu is Carol's baby brother. His presence adds to the family's daily responsibilities, requiring constant supervision in the dangerous desert environment, which includes immediate hazards like rattlesnakes under the house.

Inés is the family's elderly black sheepdog. She has lived on the property for an unusually long time. When the family arrives at the ranch, Raúl mistakenly assumes she must be the offspring of his childhood pet rather than the exact same animal.

Gabby is one of Carol's friends from her middle school in the city. She texts Carol about social events, representing the normal, Americanized teenage life that Carol feels she is missing while stuck in the desert.

Sofie is another of Carol's middle school friends from Albuquerque. Along with Gabby, she represents the urban teenage social circle that Carol longs for during her isolation at the ranch.

Mr. González is a real estate agent hired by Raúl. He visits the property to manage the details of the impending sale, making him a primary target for Serge's intense anger and resistance to leaving the land.