Tripp Spence, a widowed Virginia-based lawyer, becomes the focus of an intense IRS investigation over false bankruptcy filings tied to his wife's fatal illness. Realizing the case against him is collapsing, he flees with his 13-year-old son, Derrick Spence, a boy who loves Little League and is nearing the end of his eligibility. They relocate to Las Vegas, Nevada, and, through a corporate connection, adopt new identities: Tripp becomes Glen Simon Ryan and Derrick becomes Michael "Mickey" Jacob Ryan, presenting a backstory that they recently moved from Fort Lauderdale, Florida.
Because Derrick's new identity makes him younger by a year, he can play another season of Little League, giving them both a glimmer of hope. Tripp studies the local Little League scene and discovers the top team is coached by Tony. He arranges a private tryout for Mickey by reciting the Fort Lauderdale story, and Tony is impressed by Mickey's pitching velocity, ultimately drafting him when official tryouts arrive. Meanwhile, Glen Simon Ryan begins dating Patty, who works at Mickey's school.
Over the next year, Mickey’s development accelerates, and he quickly becomes the league’s standout pitcher and hitter, earning a spot on the All-Star team. The team advances through the district and regional brackets, drawing mounting media attention as they secure a place at the Little League World Series in Williamsport, Pennsylvania. Fears that the spotlight could reveal their true identities to the IRS weigh on Glen, who urges Mickey to quit, but Mickey refuses, determined not to let his new friends down.
After a perfect game against the Gulf States, Mickey removes the disguise glasses and witnesses his father being arrested by an IRS agent at the end of the Little League World Series Championship game, where the U.S. team faces a highly publicized Cuban team. A politician who had vowed to ban the Cuban side leaks information to LLWS officials about ineligible players on both teams. It becomes clear that the Cuban team, supposed to be from Havana, is actually made up of All-Star players from various island teams, and Mickey and Glen’s true identities are exposed.
Following the game, Glen is arrested and a press conference is held. Tripp, revealing the truth about Derrick and Mickey, joins the moment on stage as the situation unfolds. The LLWS Commissioner announces that both teams’ participation will be forfeited, and that the semifinal losers will play the next day for the championship. Derrick confesses the truth to his coach and teammates, but his friends forgive him, recognizing that their journey would not have reached its heights without him. Derrick visits Tripp at the local precinct, and, after a year in prison, Tripp is released. In the final scene, he throws a baseball to Derrick, an act that ends with the ball striking the windshield of Patty’s car.
