Li Fong (Ben Wang), a teenager from Beijing, moves to New York after his mother (Ming-Na Wen) lands a new job in the city. He brings with him a deep knowledge of kung fu, having trained under his great-uncle, Mr. Han (Jackie Chan). However, as Li moves to a new place, he makes a vow to leave martial arts behind. This promise is in respect for the tragic loss of his older brother, who was stabbed by a vengeful opponent following a tournament match.
Life in New York proves to be challenging. Li struggles to connect with others and feels like an outsider in his new environment. Things begin to change when he meets Mia Lipani (Sadie Stanley), the daughter of a pizza shop owner and the only child of Victor Lipani (Joshua Jackson), a former local boxing champion. Mia is kind, outspoken, and welcoming, and the two quickly form a close friendship. As they grow closer, Li begins to develop feelings for her.
However, not everyone is happy about this new bond. Mia’s ex-boyfriend, Connor Day (Aramis Knight), takes issue with it. Connor is a local karate champion known for his aggressive attitude. Jealous and threatened, Connor targets Li, looking for an opportunity to bully and humiliate him. Eventually, he challenges Li to settle things in a local martial arts tournament.
Li finds himself torn. His promise to never fight again weighs heavily on him, especially with the memory of his brother’s death still fresh. But if he declines, it's an invitation for Connor to bully him more. Plus, the prize money could help Mia and Victor with their pizza shop. Seeing his student’s internal conflict, Mr. Han reaches out to someone who might be able to guide Li in a different way. So he enlists the Daniel LaRusso (Ralph Macchio), a former karate champion and longtime student and friend of the late Mr. Miyagi (Pat Morita).
Daniel introduces Li to Miyagi-Do Karate and helps him rediscover what martial arts are truly about. It’s not about revenge or proving strength, but about finding balance, peace, and the courage to face life’s challenges.