at the Loeb tonight through Sunday, March 25-28

BELIEVE IT OR NOT, the musical theatre, like nearly every other part of our culture, has its own underground Hang around for a while in New York's Upper West Side or Lincoln Center or Bartley's-any place where intellectuals gather-and pretty soon you will overhear a crowd of animated types talking about those great forgone musicals. You know, shows like the late Mare Blitzstein's Juno (1959) or Bock and Harnick's She Loves Me (1963) or Stephen Sondheim's Anyone Can Whistle (1964). (Well maybe you don't know, in which case you may very well be hanging around with the wrong crowd.)

In any case, these underground musicals all have some-thing in common. They were all way too far ahead of their times when they were first done. Or they were too far behind their times. Or they were too much of their times. Or something. What I am trying to say is that they were all flops.

But, besides being commercial failures, these shows all have one other-far more important-common denominator. In nearly every case. their scores were influenced most by one man, the granddaddy of forgotten musicals, Kurt Weill. In other words if you are going to write a good flop musical, you had best throw away your Rodgers and Hammerstein albums and start tuning into The Threepenny Opera. And, even if you are not planning to start turning out such wayward masterpieces, you should turn on to Weill, because, quite simply, he has written some of the great songs of this century.

Many of these phenomenal songs can be found in Johnny Johnson, one of the most forgotten of Weill's forgotten works (It ran only two months during the 1936-37 Broadway season and has hardly been produced since), which is being revived at the Loeb this week. There are love songs and cowboy songs and anti-war songs, many among Weill's best, in this show: they must be heard.

Yet, I can't exactly say that the Loeb is the best place to hear them. While they are exquisitely rendered by John Miner's pit band below the main stage, the performers on the stage usually render them inaudibly or off-pitch or without style. And the production that surrounds the music is, far too often, more dead than alive.

It is hard for me to pinpoint exactly what has gone wrong with this show, because it so often seems headed in the right direction. Carl Fredrich Oberle's sets. which make brilliant use of projections (including a still from D. W. Griffith's Intolerance ), are perfectly conceived, as are Elizabeth Tullis's costumes and Sara Linnie Slocum's lighting. Not to mention Charles Langmuir's assured performance of the hero (an anti-war American who goes off to fight the "war to end all wars") and that swell band gliding through the original Weill orchestrations.

A lot of the problem seems to be a question of pace. The first act, where we see Johnny leaving girl and principles behind to become a doughboy, is very expository and should move like lightning if we are to keep interested. Director David Hammond is not up to the task; I constantly felt we were watching a walk-through of the show rather than a run-through or, if I may be so demanding, a performance for an audience. Polish, as they say, was lacking.

This problem, combined with the lack of singing voices, the near-fatal miscasting of the female lead, and the lack of style in much of the blocking and pseudo-choreography, gave me that feeling of death I associate with the Saturday afternoons I spent taking tickets at a theatre in Washington where so many hopeful Broad-way shows seemed to wilt up and die before my very eyes during their tryouts.

In the latter two-thirds of Johnny Johnson, though, things pick up considerably. Paul Green's epic theatre script holds up far better than one would expect in the second act's cruelty-of-war sequences and in the final act, where the hero returns home to be placed in an asylum (disease: "peace monomania") and discovers that his girl has married the capitalist-pig-next-door. It is hard to imagine any anti-war theatre being effective anymore, but about ten minutes' worth of Johnny Johnson is chilling in this respect.

These moments of potency, though, cannot cover up the fact this show neither moves nor capitalizes on its greatest asset, the score, (Only Andre Bishop's psychiatry song is captured with the bravura Weill's music requires.) It is nice that the Loeb has gone to the trouble to revive Johnny Johnson, but how could they forget that it was only the music that caused them to remember this forgotten show in the first place?