"Mrs. Doubtfire" runs through Jan. 4 at 5th Avenue Theatre . Tickets are available by calling the box office at 206-625-1900 or online at 5thavenue.org.

When the world premiere of the “Mrs. Doubtfire” musical opened at Seattle’s 5th Avenue Theatre, there was one question on everyone’s mind: Can “Mrs. Doubtfire” catch fire without Robin Williams?

And the answer?

Yes, dearie, it can.

The show is fabulous fun, especially the production numbers. Still, it’s a work-in-progress that needs polishing before its Broadway bow in the spring.

Seattle has become a testing ground for new musicals. Several shows have gone on to Broadway gold, including “Hairspray,” “Aladdin,” and “Come From Away.”

Now comes “Mrs. Doubtfire.”

Based on the blockbuster 1993 film, Broadway icon Jerry Zaks directs, with music and lyrics by brothers Wayne and Karey Kirkpatrick (“Something Rotten”) and book by Karey Kirkpatrick and John O’Farrell.

Thanks to Lorin Latarro’s brilliant choreography, the production numbers sizzle with originality. The updated book is witty and outrageously amusing —in a good way. A terrific ensemble delivers song and dance with pizzazz. Best of all, Rob McClure shines in the title role—familiar but not a copycat. His escapades invite side-splitting laughter. Even droopy types will shake with mirth.

As we know, the story waffles between hilarity and emotional depth. In the hilarity department, the new book retains some of the treasured lines from the film, while the pop culture references and celebrity impressions have been tweaked with witty one-liners and hilarious asides.

We know the storyline.

Something’s rotten in the Hillard marriage, so Miranda divorces Daniel. She gains sole custody of their three kids, but he begs for a chance to prove himself. A reluctant judge gives him a three-month reprieve.

At the beginning, the action drags a bit. The real fun doesn’t begin until Miranda decides to hire a nanny and Daniel decides to apply. A loving father so desperate to be near his children, he dons a dress and disguises himself as a woman.

In the hilarious scene, “Make Me a Woman,” Daniel seeks out his gay brother Frank (funnyman Brad Oscar) and Frank’s chic hubby, couture-clad Andre (charismatic J. Harrison Ghee). They orchestrate Daniel’s transformation into an outspoken Scottish nanny/housekeeper.

Introducing Mrs. Iphegenia Doubtfire.

The book stays faithful to the film’s plot with a few exceptions. Miranda no longer designs interiors; she designs apparel, including undergarments. She even ropes Mrs. D into being a runway model, which is a sight for sore eyes.

The classic comedy scenes remain. Mrs. D’s vacuum cleaner routine makes the cut, as does her burning D-cups. Also, the face-plunge into thick frosting to hide her identity from a prying social worker. And, of course, the frenetic, costume changes from Mrs. D. to Daniel and vice-versa.

This critic’s favorite scene, “Easy Peasy,” occurs in the kitchen, where Mrs. D. seeks cooking instructions. Suddenly, a gaggle of chefs magically appear, and together with McClure, they bring down the house with uproarious culinary shenanigans.

A close second is Mr. Jolly’s kiddy show, from the nerdy costumes to a hysterically mundane turn by Peter Bartlett as an outdated, milquetoast host who only knows one grand gesture.

No matter how you look at it, Rob McClure owns the musical. A tour de force, he’s a Tony winner in the making. If he wasn’t a superstar before, he will soon be. He delights and dazzles with comedic genius and physical acuity. He sings, he dances, he juggles, he jokes, and his timing is perfect. His vocal antics are sublime, as are the tender moments with his children. Best of all, he doesn’t trample on the other actors’ performances when they join him on stage.

The Hillard kids are outstanding: Analise Scarpaci as emotional Lydia, Jake Ryan Flynn as techie-tween Christopher, and especially Avery Sell as adorable little Natalie, who can’t keep a secret.

However, the role of ex-wife Miranda needs a makeover. Actor Jenn Gambatese has been shortchanged, her role turned into a flatbed character that bounces between boring and shrieking. Plus, her songs, as written, never capture the 11 o’clock glory we long for.

Although the production numbers are great fun, and “Make Me a Woman” could become a cult favorite, the score isn’t particularly exciting. The rap routines are okay, but the balladic duets and anthem-aspiring solos disappoint. You may leave the theater quoting clever song titles, but you might not be humming.

The transitions from high-energy numbers to somber, emotional moments are sometimes awkward, and the lead up to the ending takes too long. It diminishes the long-awaited poignancy of Mrs. D’s soliloquy about family love.

Nevertheless, the magic remains. Over a quarter of a century has passed since Williams reigned as Mrs. Doubtfire, but he remains a beloved comedy icon who blessed us with creativity, generosity and laughter.

We poppets hope that somewhere in our vast galaxy, he’s perched upon a star, smiling down on this production and cheering Rob McClure’s stellar performance.