With all of the nominees for Best Musical at this year’s Tony Awards based on TV or films — from Disney’s “Frozen” and Tina Fey’s “Mean Girls” to “SpongeBob SquarePants — it was enough to have the “serious” theater people wringing their hands about the demise of Broadway. This year, there was even encroachment into Best Play, with “Harry Potter and the Cursed Child.”

Of course, fretting of this nature this has been going on since “The Lion King” stormed the Great White Way in 1997 — or perhaps as far back as “My Fair Lady,” based on George Bernard Shaw’s play “Pygmalion” (itself based on a Greek myth). I’m not sure why some believe a musical must be completely original, but any theater publicist will tell you Job One is getting people to buy tickets, and if a known property brings in the crowds — perhaps helping fund other lesser-known works — then so much the better.

Another good reason to look to known source material is for the kids. It’s a lot easier to explain that first trip to a live show with the hook of something they’ve seen before on the screen. For me, that opportunity happened this year on the same day the Tonys took place, when I took my 5-year-old granddaughter to see “The Little Mermaid” at Boulder’s Dinner Theatre (aka BDT Stage).

Kaitlynn

Kaitlynn Greene, 5, got to meet Ariel (Lillian Buonocore) and Price Eric (Cole LaFonte) after a production of ‘The Little Mermaid,’ playing now at Boulder’s BDT Stage.

As I’d learned with some of my own children, dinner theater is staggeringly popular with the little ones. Once they get the concept of having lunch or dinner first, seeing the actors double as the waitstaff and with dessert at intermission, they’re usually asking me when we’re going again.

It’d been a little while since I’d seen a show at BDT Stage, but with 40+ years under its belt putting on four musicals a year, the theater has a strong reputation for high-quality shows and a great menu. “The Little Mermaid” was no exception.

Based on the Disney film that was itself based on a Hans Christian Andersen tale, “The Little Mermaid” is a classic princess romance, with dreamy Ariel pining for life above the waves and with her eyes on a young prince who’d recently fallen overboard. In addition to the small matter of the large fin she has instead of feet, the conflict comes from the usual disapproving parent (King Triton) and a wicked sea witch named Ursula.

Anyone who’s ever been around little kids has probably seen the Disney version a few dozen times, so even without the water it’s easy to recognize the fusspot major domo Sebastian the crab, Scuttle the seagull and Flounder the fish.

“How are they going to do all the water, and the fish?” Kaitlynn wanted to know as we drove to the theater. The answer was a lot of clever stage effects and wonderful costumes that include hand puppets matching the sea creature in question. It seemed to take just a short amount of time to get absorbed in the world created on stage, and Kaitlynn was soon in the show’s thrall. She was also highly entertained by seeing how things were done, watching the entrances and exits and pointing out other movements by the characters.

In other words, she was learning about live theater and how different it is from movies and TV. When Flounder appeared at intermission to refill our water, she was unfazed — already completely at ease with the dual roles the actors were playing and ready to pose for a picture with the guy in the fish costume (a very friendly Chas Lederer).

This production features some strong performances by newcomer to BDT Lillian Buonocore as Ariel, BDT veteran Alicia K. Meyers as Ursula and Anthony P. McGlaun as the Jamaican-accented crab. Elaborate costumes, dance numbers, sets, lighting and other effects make for a memorable performance perfect for younger children new to the theater. And for those of us who’ve seen the film a few times, it was fun to revisit the story and enjoy a day with someone special.

“The Little Mermaid” runs through September 8, so there’s plenty of time to get down to Boulder and see it. Little ones should feel free to dress up for a night (or matinee) on the town and stick around after the show for photos with cast members.

If you go:

What: “The Little Mermaid,” musical based on the Disney film

Where: BDT Stage, Boulder

When: Through Sept. 8

Tickets: bdtstage.com or 303-449-6000