Matt is a seventh-grade boy adopted by an American family after being airlifted out of Saigon. Haunted by fragmented memories of war and the biological family he left behind, he struggles with feelings of isolation and guilt in his new, peaceful environment. He finds outlets for his emotions through pitching for the middle school baseball team and learning to play the piano.

Elizabeth is Matt's adoptive mother. With her blonde hair and summery demeanor, she contrasts sharply with Matt's dark memories of Vietnam. She provides a deeply loving, patient presence and encourages Matt to pursue music as a way to process his trauma.

Michael is Matt's adoptive father who works in the medical field. He bonds with Matt primarily through sports, frequently reassuring him that he is the family's Most Valuable Player. He carries his own unresolved guilt about taking a medical deferment instead of serving in the war.

Phang My is Matt's biological mother in Vietnam. She made the agonizing decision to hand Matt over to American airlift soldiers, instructing him to survive. Her choice leaves Matt conflicted about whether he was saved or abandoned.

Huu Hein is Matt's biological younger brother who remained in Vietnam. He suffered devastating physical trauma from an explosive, leaving him with stumps instead of limbs. Matt carries an overwhelming sense of responsibility for his brother's condition.

Rob is a seventh-grade student and a player on the middle school baseball team. He relentlessly bullies Matt using racial slurs and holds Matt personally responsible for the death of his own older brother in the Vietnam War.

Tommy is Matt's young adoptive brother. He has blonde, curly hair and a consistently sunny disposition. He serves as a stark reminder of the peaceful, sheltered childhood Matt did not get to experience.

Matt's biological father is an unnamed American soldier who lived with Phang My in Vietnam. He promised to return to his family after the war but never did, leaving Matt with intense feelings of resentment.

Jeff is a former combat medic who now works at the same hospital as Michael. He teaches Matt how to play the piano and introduces him to a local group of Vietnam veterans, providing a safe space for Matt to process his history.

Coach Robeson is the dedicated leader of the middle school baseball team. He strongly enforces a culture of respect and teamwork among his players before a serious medical diagnosis forces him to step away from his duties.

Chris, once known as "Whirlin' Will" for his pitching skills, is a young Vietnam veteran who now uses a wheelchair and has extensive facial scars. Coach Robeson selects him to take over the middle school baseball team.

Mr. Brennan is Rob's father. He carries profound grief over losing his older son to the Vietnam War, a trauma that severely impacts his family's emotional stability.

Celia was Chris Williams's high-school sweetheart. She left him after the war fundamentally changed him, adding to the veteran's deep sense of loss.

Coach Louis is an assistant baseball coach at the middle school. He steps in to manage the team and break up physical altercations between players during Coach Robeson's absence.

Mr. Chambers is a school teacher who temporarily helps run the baseball team. His lack of focus during practice allows bullies to covertly target Matt.