Lights still shone on the stage. The house was dark. “The Sound of Music” had just finished.

Kurt Hellerich, then a freshman at Central High School, ran center stage in blue shorts and black socks up to his knees, a fresh young actor in his first musical, in his first role as Kurt VonTrapp.

He took a bow.

The audience cheered, their faces a blur, as the cast took their final bow together.

Then, the curtain fell.

“... That was the moment that changed everything,” says Kurt, now 17 and a junior. “And I got stuck.”

It was nothing like winning a volleyball game, nothing like winning at basketball.

“It was something that felt like I was supposed to do.”

Just months before, Kurt had no thoughts of acting or bowing on opening night. For some reason, though, he decided to audition for the school musical. Maybe, he thinks, as a member of the choir, he was expected.

So he showed up with a song from “Oliver,” feeling timid.

But Ryan VanDyke, Central’s theater teacher and director, saw something sparkle in the young man on stage, and soon, Kurt was one of three freshman cast in “The Sound of Music.”

Since, he’s been a sponge, Mr. VanDyke says, showing up early at rehearsals, always anxious to do more. Kurt has been a part of every play and musical since — “War of the Worlds,” “Godspell,” “Brigadoon,” and many more.

“Kurtis has a very watchable quality to him,” Mr. VanDyke says.

And he still has that sparkle when he performs.

“He does,” says Kurt’s mom, Amy Auxier. “He lights up when he’s on stage ... he comes alive.”

And Kurt’s mom and drama teacher aren’t the only ones who’ve noticed.

Earlier this month, Kurt attended the Missouri Thespians Conference at the University of Missouri at St. Louis, where he auditioned along with 1,500 other students for a role in an All-State Production of “A MidSummer Night’s Dream.” He got the role of Demetrius.

He’s also in other activities, taking four AP classes.

“It’s really kicking my butt, to be quite honest ...” he says.

But most of his time goes to the theater, and it’s a life he always wants to live. Kurt’s hoping to be accepted into the theater conservatory at Webster University in St. Louis. It’d be great to make it on stage in New York, but really, Kurt says, “I don’t need stardom.”

He just wants the ability to make a living in the art form he loves and stay stuck, as he puts it, in those moments where he’s looking out at the audience who’s been with him through a performance, and they’re clapping, and he’s bowing and the curtain falls and, Kurt thinks, it’s like nothing else.