Sandy Duncan was the first guest star on "The Muppet Show," and her appearance Friday Night with the Utah Symphony brimmed with the same zany, spontaneous energy that made Fozzie Bear and Gonzo stars. Sandy and her co-stars Guy Stroman and Don Correia (who is also her husband) haven't forgotten the true joy of musical comedy.

Stroman was the first on the stage singing a line from "The Music and the Mirror" from "A Chorus Line." Stroman continued the song, then Duncan danced on stage, patting the conductor on the behind as she passed.The first medley included Irving Berlin's "A Couple of Song and Dance Men" and "A Couple of Swells" as well as "Two Fellas" from "Cabaret." Their choreography, though at times silly, remained energetic and cute throughout the show.

The corny between-medley patter naturally set up each song, and the trio's most striking feature was how genuinely relaxed and happy-go-lucky they were. Their enjoyment came through as each recounted "how it all began," with the three acting out a charming tribute to Duncan's first dance class. They used the song "One Step" from the Off-Broadway hit "Starting Here, Starting Now."

Duncan told the story of the night she first met Stroman while on the road doing Peter Pan. ("I was really depressed. The harness had banged me into the wall a few times that night.") As they reminisced, the two launched into "Big D" from "The Most Happy Fellah," which tells how two people from Dallas can instantly recognize one another by their phraseology. ("Can you say `tell you what' again?")

Both Duncan and Stroman are Texans, but Sandy didn't meet her husband till she came to Los Angeles. Correia began the story of how they met, and Duncan corrected his memory periodically until the two fell naturally into "I Remember it Well" from "Gigi."

After Duncan sang "How Long Has This Been Going On," her husband did an energetic version of "All I Need is the Girl" from "Funny Girl" which could only have been improved had he been wearing his tap shoes.

One of Duncan's best numbers, as well as the most interesting choreographically, was the biting Rodgers and Hart song "Ten Cents a Dance." Both Correia and Stroman danced abusively with Duncan until Correia returned, rescued her with a perfect waltz, then abruptly left.

Of course, any trio doing Broadway tunes will do the "Tinhorn Trio" from "Guys and Dolls," but this bunch also did a bi-gender version of "You Gotta Have a Gimmick" from "Gypsy."

They ended with a medley based around the Cander and Ebb song "Show Stopper." Stroman's show-stopper was "Trouble" from "The Music Man," Correia's was "Singing In the Rain" (with tap shoes) and Duncan became a little boy and sold "Never-Never Land."