“Play the pauses,” the stern, English-accented music teacher tells his violin student (Wenwen Han as Meiying). Watching, and clearly paying close attention, is Dre (Jaden Smith, son of Will Smith and Jada Pinkett Smith), just arrived in China from Detroit, where he has left behind everything he knows and cares about. Young Smith himself was paying attention, too. Watch him hold the screen even when his character is not doing anything special. Smith knows better than many adult actors how to play the pauses. In his first starring role, his deft and engaging work is the heart of the film.

The first “Karate Kid,” released in 1984, starred Ralph Macchio as a teenager who gets martial arts lessons from a handyman (Pat Morita) and takes on the guys who have been bullying him at a big climactic karate match. There were two sequels with Macchio and then “The Next Karate Kid” starring future Oscar-winner Hilary Swank. In this version, Smith plays a 12-year-old who moves to China when his mother (Taraji P. Henson) is transferred to Beijing. At first he feels lost. Bullies attack him, leaving him humiliated and angry. When the maintenance man, Mr. Han (Jackie Chan) comes to his rescue, Dre asks for lessons. And when Mr. Han commits to have Dre compete in the kung fu championship in just three months, it’s time to cue up the training montage and zoom in on the Great Wall.

Even if they had not already made this movie four times, there would not be any surprises in the story. But the movie can still surprise us with its specificity of choices and the connections of its characters. Chan, who has too often been ill-served in his American movies, is well-suited to the role of the taciturn mentor. His one fight scene is as electrifying as ever and should bring a new generation of viewers to his Chinese classics. Smith has his father’s confidence and charm on screen. And it is a pleasure to see the match of the dedicated, courageous young man and the wise teacher work as well for the performers as it does for the characters.