In this third film of the Bad News Bears series, Tony Curtis plays a small time promoter/hustler who takes the pint-sized baseball team to Japan for a match against the country's best little league baseball team which sparks off a series of adventures and mishaps the boys come into.
- The hapless American Little League baseball team, the Bears, see the Japanese junior baseball champions on television. The Japanese team has invited Americans to play them, but no team has accepted the challenge. The Bears decide to answer the call and go on a local morning talk show to generate support.
Meanwhile, local hustler and con artist Marvin P. Lazar (Tony Curtis) contemplates his debts, sees the Bears on television, and gets an idea that he later pitches to his associate, Louis the Gambler (Lonny Chapman): For $10,000, Louis can invest in Marvin's plan to take the Bears to Tokyo and broadcast the game nationally on American television. Louis declines because Marvin already owes him money. After Louis leaves, the Bears arrive to meet Marvin at his office, who falsely implies that he has already raised the money. Giving the children contracts, Marvin claims that their parents have approved and explains that he can promote the game and make them famous as both their manager and new coach. One team member, Ahmad Rahim (Erin Blunt), informs Marvin they have to take his six-year old little brother, Mustapha (Scooty Thornton), with them.
Several days later, the Bears arrive in Tokyo and meet the Japanese team and their coach, Shimizu (Tomisaburô Wakayama), before proceeding to their hotel. Marvin gives the hotel two credit cards. After setting up an exhibition practice inning with the Japanese team for the next morning, Marvin tries to find a TV network to cover the event and a company willing to make an endorsement deal.
At the exhibition, Marvin suggests different ways to write the Bears' story to Eddie (Jerry Ziesmer), an American television network journalist. The Bears' star player, Kelly Leak (Jackie Earle Haley), hits a home run, but the rest of his teammates play terribly and Japan scores ten runs to the Bears' one. Eddie tells Marvin that he will try to promote the game but warns that no one in the U.S. wants to see an American team get beaten.
On his way back to the hotel, Kelly sees a beautiful Japanese girl (Hatsune Ishihara), and follows her to her music lesson. He approaches her afterwards but she speaks only Japanese. He follows her home and continues his attempts to communicate with the help of a Japanese-English dictionary. Kelly asks the girl to dinner and learns her name is Arika.
Back at the hotel, Marvin finds it more difficult to promote the game than he anticipated and he is forced to confront his lies. Hotel management figures out that Marvin has no money, cuts up his credit cards and insists that he pay in cash. Meanwhile, the Bears realize Marvin misled them; he has not set up any games or television coverage. Disappointed, the Bears berate Marvin for lying but Mustapha says he still likes the coach.
With the team stuck in Japan, Marvin is determined to make money. He bullies his way into a wrestling match with Japanese champion Antonio Inoki; although Marvin tries to dive from the wrestler, Inoki throws him around the ring. Concerned for Marvin's safety, Mustapha intercedes in the match by jumping on Inoki's back and biting his leg. The boy's teammates join in and they overcome Inoki. Marvin is declared the winner and earns enough money to cover their hotel stay. The unusual wrestling match is reported in the press and the Bears start garnering media attention.
As the Bears and the Japanese team ride the train to their game location, Marvin realizes Kelly is missing. Back in Tokyo, Kelly and Arika walk around the city and get to know each other, despite the language barrier. After the two teams arrive at their destination, Shimizu observes Marvin's efforts to generate media interest and expresses disdain for Marvin's artifices despite his lack of speaking English. Later, Marvin concedes that he can be obnoxious, but argues that he doesn't want to miss out on the opportunity; if his efforts to court the media are successful, Shimizu and his team will benefit, too. When Marvin points out that he and Shimizu don't have to like each other to work together, Shimizu gives in. Shimizu and the Japanese all-stars win a nationally televised amateur talent game show and secure an endorsement deal with a baseball bat company. Meanwhile in Tokyo, Kelly and Arika share their first kiss.
Sometime later, Marvin announces that the Bears are making money and presents them with new uniforms, ignoring protests that they are happy with their current outfits. As the Bears leave to watch a baseball game, Mustapha stays behind to be with Marvin, but Marvin shoos the little boy away to keep a private appointment. Marvin emerges from a massage parlor to find Mustapha waiting for him. When the boy asks Marvin why men and women kiss and how babies are made, Marvin answers as best he can.
In Tokyo, Kelly finds Arika at pinball arcade and meets her disapproving father, who forces Arika to send Kelly away. Later, Ahmad calls Marvin an unscrupulous, manipulative and unfeeling "loser," and Marvin considers the accusations. The next day, Marvin runs into Louis. The gambler introduces him to his boss Locke (Robert Sorrells), who is in town with three teenage baseball superstars from Texas that could play for the Bears and help them win. Louis and Locke offer to place a $5,000 bet on the Bears for Marvin in Las Vegas, Nevada; since the odds are 25 to one for the Japanese team, Marvin could make a lot of money.
On game day, Marvin introduces the three Texas players, but the Bears don't want help, claiming that Marvin pushed them to be underdogs and now they have something to prove. However, Marvin wields his authority and predicts that with the Texans on the team, the Bears will win the game and be national heroes. If the Bears lose, they will get nothing. As the team heads to the dugout, Ahmad admonishes Marvin. The game begins with the Texans batting and pitching well, but the Bears shun Marvin in the dugout. When Mustapha tries to comfort him, Marvin yells at the boy to leave him alone. Soon, the Texans exhibit unsportsmanlike behaviors and a fight ensues, involving the Bears, the Japanese team and audience members. After police end the brawl, stadium officials cancel the game. However, the television network director informs Marvin he will leave the cameras rolling until 4:00 p.m., so Marvin can still get another game on the air.
Learning that Shimizu left his team because the players participated in the fight, Marvin finds his fellow coach and they commiserate in a hotel, but they look out the window to see their two teams playing for fun in a neighborhood lot. The coaches join their players and everyone enjoys himself except Kelly, who is having trouble concentrating. Suddenly, Arika arrives and Kelly hits a home run. The two teenagers run into each other's arms and kiss.
When the network director (George Wyner) sees the game, he insists that the players return to the stadium, adding that Marvin is contractually obligated to deliver a game, but Marvin does not consent. Although Marvin suggests that the director ask the boys directly for their approval, the man threatens to sue the coach for breach of contract. Unfazed, Marvin announces that he is done promoting and the boys cheer. Taking Shimizu aside, Marvin suggests that the teams play together in Cuba next year.