"Barnum," the Cy Coleman musical based on the life of America's biggest 19th- century showman, played for two years on Broadway in the 1980s and won several awards. But in the new production at Army Community Theatre its bones are showing.

It's a small musical for primarily two voices, all pumped up to look like something much grander. P.T. Barnum himself might well have called it "humbug." After all, he's credited with the phrase "There's a sucker born every minute."

In this production, neither the circus acts nor the life path of the title character are exciting enough to make it the grand spectacle it needs to be.

At the show's core is the character of Barnum (Rob Duval), a larger-than-life promoter who creates a world of Technicolor hype and exaggeration. Anchoring him in practical reality is his wife Charity (Stephanie Conching) and, between them, they carry most of the show's musical numbers.

There is a short-lived romantic triangle involving the singer Jenny Lind (Jaime Blu Craycroft) that bridges the intermission and adds some operatic coloratura. But the weight of the music rests on Conching — who has a pleasant and capable voice — and Duval — who pushes hard, but goes progressively flat as the evening progresses.

The part — with its wordy patter song — plays as a close cousin to con-man professor Harold Hill in "The Music Man," and earned Jim Dale (recently known for recording "Harry Potter" audio books) a Tony Award in 1980.

Barnum's role is the long pole that holds up the entire show's circus tent and demands singing, dancing and a great deal of physicality. Duval earns points for stamina but doesn't give the part the stature that it needs.

The original production pleased Broadway audiences 30 years ago with the circus acts that provide a diverting background and fill in the transitions between scenes. For extra showmanship, the Barnums' domestic squabbles are appropriately announced as "now appearing in the center ring." But without real circus talent to draw on, the ACT production fills in with some basic juggling and gymnastic moves that suggest the proper milieu, but don't get much beyond a repeated backflip.

Director Grace Bell does provide a big splash of color and movement for the big finale, but it comes too late to validate Barnum's life as a promoter — as it must in the show's book.

Musical director Peter Rucci and vocal coach Larry Cross get consistently good sound from the orchestra and chorus — although their intelligibility and dance work fall short. Lynn Nakamoto as the "oldest woman in the world" and Jeff Tabisola as General Tom Thumb get featured solos.

The production also looks good with a big-top backdrop, lots of colorful costumes, and a 20-foot-tall elephant puppet that swings its trunk like a musical pendulum.

Joseph T. Rozmiarek has been reviewing Hawai'i theater since 1973.