Like the cosmic convergence that brings four dead lads out of their 40-year limbo for the "biggest comeback since Lazarus," all the elements align to make "Forever Plaid" the perfect debut show for the new Cosmopolitan Cabaret, which opened Sunday at 10th and K streets.

It's smart, good-looking and sounds great – and that's just the cabaret. The show is all that, plus funny, touching and old-fashioned – in a good way. "Forever Plaid" pays homage to and makes fun of the musical guy groups of the 1950s and '60s, their precise harmonies, their sharply stiff choreography, their sometimes inane banter between songs. It mocks them, yes, but gently, and with love.

The showroom, with tables on the main floor and elevated rows of seats (with drink shelves in front of them) stretching back is planned to offer pre-show drink service by the adjacent Cosmo Café. On Sunday, patrons got their own drinks – those who could.

The bar seemed over-taxed and several theater- goers still waiting in line were told the show was starting and sent into the showroom drinkless.

Written by Stuart Ross, "Forever Plaid" tells the story of four guys – Sparky (Chris Crouch), Jinx (J.D. Daw), Smudge (Sean Patrick Hopkins) and Frankie (Justin Packard) – who loved to sing. They met as members of their high school Audio Visual Club – the "projector sector" – and formed a singing group in the vein of the Four Freshmen. Their budding career came to a crashing halt when, on the way to their first big gig, their car was smashed by a busload of Catholic schoolgirls on their way to see the Beatles on "The Ed Sullivan Show." The girls were unharmed; the boys died.

Just as the Beatles would figuratively end the old-style foursome singing groups, they literally ended the Plaids. That is, until this magic moment when the Plaids get one chance to perform that concert they never got to do in 1964.

"Forever Plaid" is not a traditional musical with a story and some songs mixed in. "Forever Plaid" has a lot of songs with a little story mixed in. A taped intro to the program, read by Katherine Cannon, sets the scene for the performance that follows.

Beginning with "Three Coins in the Fountain," which is performed … well, as if the boys hadn't sung it in 40 years, the concert they would have done proceeds through two dozen or so pop hits of their time.

As the quartet loosens up and the guys find their voices, the old choreography comes back; they relax; and their individual personalities come through. Frankie (Packard) is the leader, the gentle prodder who gives encouragement to sometimes reluctant performers. Smudge (Hopkins) is the serious-looking, glasses-wearing bass. Sparky (Crouch) is a cut-up and the group's fine baritone. Jinx (Daw) is a high tenor, who probably would have been the Paul (as in McCartney) of the group, the "cute one."

All four men are outstanding singers and excellent actors. Near the end of the show, when Frankie rhapsodizes about the "perfect chord," the moment when four voices merge into one, Packard packs so much emotion into the speech that you truly believe he believes it. Sunday night, when Daw sang "Cry," the song that put Johnnie Ray at the top of the charts in 1951, he stopped the show. The audience didn't just applaud – it cheered.

A three-minute re-creation of "The Ed Sullivan Show," complete with a barking seal, a juggler, a couple of plate-spinners, an accordionist playing "Lady of Spain," the Singing Nun, Topo Gigio and Señor Wences, was a high point with its frenetic energy and obvious affection for the television show.

"Forever Plaid" could hardly be better suited to the 200-seat Cosmopolitan Cabaret if it had been commissioned for it. But it wasn't. Its first cabaret run was in New York in 1990, when it was nominated for a Drama Desk Award for outstanding musical revue. (A movie starring David Hyde Pierce and directed by creator Ross will be released later this year.)

The stage set, props and costumes for this production are from the Pittsburgh Civic Light Opera, whose Cabaret Theatre opened in 2004 with the show.

It's an intimate little musical, with only a piano (played by musical director Chris Schlagel) and a bass (played by Chelsea Gordon) as accompaniment. But it's a little more elaborate than it appears, requiring a unity in lighting (designed by Steve Odehnal) and sound (designed by Robert Sereno) as tight as the harmonies in the vocals. Director Guy Stroman seems to have a tuning fork and a stopwatch on the show, beginning to end.

The show has an open-ended run at the cabaret – tickets are being sold through Feb. 1 at least – but why wait?

Call The Bee's Jim Carnes, (916) 321-1130.