Jon Viktor Corpuz spends virtually all of The King and I as Prince Chulalongkorn, the heir to the throne, not the monarch, but in one sense he does always have the top job: he’s king of the kids. I don’t mean to suggest that Corpuz lords it over the eleven other Royal Children. Those young actors, of whom I shall write more extensively at a later date, are sufficiently self-possessed to need no offstage bossing. But there’s no question that, onstage, Corpuz’s character takes precedence.

“As heir to the throne, the Prince comes first,” Corpuz told me the other evening in his dressing room, as he sipped soup in preparation for a performance. “Even Mrs. Anna had to defer to him.” He added: “He’s a teenager, but everyone around him, even the adults, has to be a ‘yes’ person. In that sense, I think of him as the Justin Bieber of Siam.”

In his own family, Corpuz is the youngest sibling, not the oldest. He grew up in Tampa, Florida, an only boy with two sisters. “It was a typical Filipino household,” he said. “There was always music. We even had a karaoke machine.” When Corpuz was 8, he got the lead in a new musical put on by a community group. “That was where I got bitten by the musical-theater bug,” he confessed. Semi-professional theater gigs followed, including both musicals and plays. The first big professional show he saw was Cats.

When Corpuz was 15, he got a professional theater job in Staten Island. “My family and I spent the summer after that living in New York,” he said. “My parents were trying to see just how serious I was about performing. When they saw I wasn’t kidding, we moved to New York for good.” They landed in Queens at first; now, they reside in the Washington Heights neighborhood of Manhattan.

Corpuz auditioned for LCT’s The King and I last summer. “I went in six times before I got the part,” he said. “The real-life Prince was 15 when his father died.” He continued: “Many professional productions cast younger actors in my part who are 12 or 13 years old, so the Prince’s music is written higher than my voice is now. Before I auditioned, I had the music taken down a step, so I felt more comfortable singing it.”

Corpuz is a senior at the Professional Performing Arts School, a New York City public school that tends to smile more indulgently on students who work professionally than do some other arts academies in Gotham, and whose alumni include, if not Justin Bieber, then one of the Beeb’s predecessors in teen-pop spectacle, Britney Spears. “It’s a little bit of a struggle to keep up with my schoolwork while rehearsing and previewing in a big show,” Corpuz said. “But I’m so grateful to be in this production that I feel I can handle the challenges.”

Including the responsibility of presiding over 11 kids? “Yes,” he said. “I always wanted a little brother or sister in my own family. So they are like the siblings I never had.”

Brendan Lemon is the American theater critic for the Financial Times and the editor of lemonwade.com.