Danny is a sixteen-year-old biracial teen who feels caught between his white mother's affluent world and his absent Mexican father's heritage. He is a talented but psychologically blocked baseball pitcher who attends Leucadia Prep on scholarship. Struggling with his identity and lack of Spanish fluency, he digs his fingernails into his own skin when stressed. He desperately hopes to reconnect with his father, whom he believes moved back to Mexico.

Uno is a physically imposing, biracial teen who dominates the local stickball games in National City. He relies on his street smarts and physical strength to maintain respect among his peers. Living with his mother and a strict stepfather, he feels a pull between his immediate surroundings and the possibility of a different life in Oxnard with his biological father.

Senior is Uno's biological father who lives in Oxnard with a new family. Having overcome a past filled with violence and addiction, he now focuses on hard work and his religious faith. He makes monthly trips to San Diego to build a relationship with Uno and offers him a chance to move to Oxnard if he can save enough money.

Sofia is Danny's confident cousin who operates as a social hub in her neighborhood. Though only a year older than Danny, she acts much more mature and actively shields him from local trouble. She presents a tough exterior but occasionally questions what the future holds for teens growing up in her area.

Wendy is Danny's white mother who recently moved her children from National City to the affluent coastal town of Leucadia. She works hard to provide opportunities for her children, including securing Danny's prep school scholarship. Currently, she is spending the summer in San Francisco, hoping her new relationship will bring stability to their lives.

Liberty is a teenage girl who recently relocated to the United States from Rosarita, Mexico. She does not speak English, which mirrors Danny's inability to speak Spanish, yet the two form a quiet, mutual attraction. She lives in National City because her white American father secured her entry, though he remains absent from her daily life.

Javier is Danny's absent Mexican father who disappeared three years prior. Danny idolizes him and writes him mental letters, convinced Javier left because he could not handle having a half-white family. His brothers and former wife keep the actual circumstances of his disappearance hidden from Danny.

Ray is Danny's uncle, a man who commands immediate fear and respect on the streets of National City. He is highly protective of his family, particularly Danny, and is quick to use intimidation against anyone who wrongs them. He shares many behavioral similarities with Danny's absent father.

The Mexican Scout is a large, quiet man who frequently watches amateur baseball practices. Danny notices him in the bleachers evaluating high school players and later sees him observing local games in National City.

Kyle is a high school senior and the star baseball player at Leucadia Prep who anticipates a Major League draft pick. He possesses professional-grade talent and benefits from the active presence of a wealthy, supportive father. To Danny, Kyle represents the ideal life and athletic success he feels he lacks.

Uncle Tommy is Sofia's father and the most responsible member of the Lopez brothers. He works hard to provide for his family and eventually secures a high-paying temporary job in Las Vegas. He offers Danny a place to stay for the summer and acts as a stabilizing force in the extended family.

Manny is Uno's younger brother who recently returned home from a group facility. He experiences developmental challenges and relies heavily on Uno for entertainment and protection in the neighborhood.

Loretta is Uno's mother, a woman who is trying to build a fresh start with her new husband, Ernesto. She frequently expresses frustration with Uno's behavior and speaks harshly about his biological father.

Ernesto is Loretta's husband and Uno's strict stepfather. He demands absolute obedience in his household and frequently uses harsh language to assert his authority over Uno.

Randy is a wealthy, white professional who is dating Danny's mother. He pays for Wendy and Julia to spend the summer in his large San Francisco apartment and frequently offers financial support to Danny's extended family.

Julia is Danny's sister who fully embraces the opportunities presented by their mother's new boyfriend. While Danny heads to National City, she spends her summer taking dance classes in San Francisco.

Cecilia is Uncle Tommy's wife and Sofia's stepmother. She effectively runs the household while Tommy works and maintains a deeply supportive, maternal bond with Sofia.