For about 90 minutes, five performers, backed up by a combo of three, sing 31 George Gershwin standards in "Rhapsody in Gershwin," the New York-born revue that opened last night in the Kennedy Center's Terrace Theater. Combine them as you will, those figures don't add up to a great deal.

The show is one of a series of revues concocted for the King Cole Room of the St. Regis Hotel, and perhaps in supper-club surroundings with a drink or two to nurse along, it would seem less insubstantial. Transported to the Terrace Theater, it looks vaguely out of place and just a little lost. Intimate as it is, the Terrace is not a lounge, and the three potted palms on stage won't fool you into thinking otherwise.

Of course, any show that gives you "Strike Up the Band," "I Got Rhythm," "Fascinating Rhythm" and "S'Wonderful" -- and all of them in the first 10 minutes -- is not a total loss. A Gershwin tune is the top of the line. And brother Ira was no slouch in the lyrics department, either. Yet, most of the numbers seem just a little flavorless this time around.

The singers -- Tina Fabrik, Ira Hawkins, Audrey Lavine, Kevin Marcum and Adrienne West -- are certainly competent enough, and they seem to be enjoying their work. But none of them really gives much evidence of possessing a stage personality that might make us sit up and take notice. The interpretations are slick and efficient and unsurprising.

Billy Wilson has staged the offering in a similiar spirit. There is a fair amount of choreography, but mostly it is the kind of general moving-around for nondancers that the off-Broadway revue, "Scrambled Feet," spoofed heartlessly as "sham dancing."

No, it is Gershwin who is doing the work in this show, and if you don't go expecting revelations, the evening provides some occasional pleasures: Lavine's "A Foggy Day," Fabrik and Hawkins' "Our Love Is Here to Stay," West's "How Long Has This Been Going On?" and Marcum's "Summertime." The last is part of a medley drawn from "Porgy and Bess," for which all five performers manage to summon up some of the sass and passion that is noticeably lacking elsewhere.

"Rhapsody in Gershwin" will play for two weeks, at which time it will make way for another St. Regis revue, "Rodgers and Hammerstein and Lerner and Loewe." Let's hope those gentlemen get a little more help than George has been given.

RHAPSODY IN GERSHWIN, songs by George Gershwin; directed by Billy Wilson; musical direction, Keith Herrmann; lighting, Helen Anne Gatling. With Tina Fabrik, Ira Hawkins, Audrey Lavine, Kevin Marcum, Adrienne West.

At the Terrace Theatre through Nov. 1.