SUPERMAN -- At the AMC Carrollton, K-B Langley, K-B Silver, Roth's Tysons Corner, Showcase Fairfax Circle, Showcase Oxon Hill, Showcase Pike and Springfield Mall and Uptown in 70 mm and Dolby stereo.

They just couldn't leave super enough alone.

The first "Superman" film, with its whammo charm, stunned modern audiences with such a shock of wholesome, naive, good-humored virtue that all that was required for a sequel was more of the same.

And "Superman II" has its moments. But they are all in the introduction, when the earlier picture is summarized and the basic characteristics of Superman/Clark Kent and Lois Lane, still played radiantly by Christopher Reeve and Margot Kidder, are restated. It's good to know that the reason the mild-mannered reporter isn't aware that terrorists are threatening to destroy Paris is that he's been at home reading Dickens; and that when he remarks that this news is terrible, he has his editor, Perry White, to explain to him, "Yes, that's why they call them terrorists."

But the thrust of the film is to escalate the Superman idea to the point where the charm is no longer visible. A snide and knowing viewpoint has left a cloud of smudge over the original clean satire.

One premise of the Superman idea has always been that he's a powerful resource to preserve "truth, justice and the American way." A high point of the original film was that after he captured the villians, he turned them over to police with the admonition, "See to it that they get a fair trial."

Another is that he's hopelessly stalemated in his respectfuly courtship of the dynamo reporter Lois, because Superman's real-life disguise is too mild a character to engage her fancy.

Well, in this story, there doesn't seem to be any American way left; Clark Kent chooses macho over manners in a public brawl, and the romance is -- consummated. Yes, kiddies, you get to see astronauts squashed like insects, the president of the United States groveling on his knees and surrendering the entire universe to space villians, and Superman and Lois nesting together in postcoital (but premarital) bliss.

The cinematic skies are cynically full of suggestive adventurers, and the reappearance of Superman, in all his original purity, was an engaging novelty. But it's just because Reeve and Kidder remain true to the brightness of their chracterizations under the new circumstances that the tone of the film, directed by Richard Lester and written by Mario Puzo, David Newman and Leslie Newman, seems to be sneering at them.

Typical of this is a long scene in which the two reporters, having been assigned by their editor to share a vulgar "honeymoon suite" at Niagara Falls for a feature assignment -- the Daily Planet has also gone scummy -- are stranded mid-screen while a bellman leers at them and makes dirty jokes.

This is a sad spectacle for audiences waiting to cheer virtue triumphant. If Superman has succumbed to sleaze, who's going to save the world?