The continuing appeal of "Grease" is astonishing. It is Broadway's longest running show and 1978's highest grossing film. Yet it's nothing more than a cartoon about high-school kids in that exotic era two decades ago. Many of its fans were not yet born two decades ago.

The movie obscured the remoteness of the period by giving "Grease" a title tune with a '70s disco beat. It also set "Grease" in antiseptic suburban splendor that belied the essential greasiness of the subject and may have made it more palatable for today's youngsets.

Now the play has returned to Washington for the umpteenth time, at the Warner, and there is no question that it is more authentic and more watchable than the film.

This new version of the show begins ominously. A recorded version of Barry Gibb's inane title tune from the movie is played as the overture. What this song has to do with the '50s is anyone's guess.

Once the actual show begins, however, most of the movie's distortions are shucked off. Douglas Schmidt's set is properly grungy. And the direction by Tom Moore and choreography by Patricia Birch-restaged here by Thomas C. Smith and Cynthia Darlow - move like clockwork compared to the clumsy direction of the film.

It's particularly pleasing to see the dancing restored. This high-school prom looks like fun; the movie's prom looked like an air raid drill.

On opening night the cast members were having considerable difficulty projecting their voices through some rather uncooperative microphones. A number of lyrics were lost.

The non-musical parts of Jim Jacobs' and Warren Casey's script are negligible, so the show cannot afford the loss of their lyrics.Presumably the wrinkles will be ironed out during the two-week run.

The cast certainly appears capable. Rex Smith, a budding teen heartthrob, has the John Travolta role, but that role was pumped up in the movie to accommodate Travolta's stardom. The stage show is much more of an ensemble effort. As soon as this ensemble is able to make itself consistently heard, it'll do fine.

It still can't explain, however, why "Grease" keeps going and going.