The Eisenhower Theater, serving as an opera house for only the second time in its history, was host to its first wild operatic triumph last night. The opening night audience for Gilbert and Sullivan's "Ruddigore" wore itself out with laughter and applause for the Washington Opera's new production -- a brilliant exercise of musicianship, wit, style and painstaking attention to the smallest details.

"Ruddigore or the Witch's Curse," now in its centennial year, is not one of the top five Gilbert and Sullivan collaborations. It is relatively seldom produced today for perfectly sound reasons -- including technical difficulty, expense and lack of the presold audiences that will always flock to "The Mikado" or "H.M.S. Pinafore." But in this production, which will run through January, "Ruddigore" seems as bright and enjoyable as anything that ever came from the fluent pens of those gifted partners.

"Ruddigore" is the reductio ad absurdum of Victorian melodrama -- a work full of sinister noblemen, ghosts and ghouls, unspeakable crimes, an ancestral curse and betrayals of the most perfidiously despicable sort. It runs constantly to extremes. It is (as a melodrama should be) also full of surprises. The abduction of maidens is a recurrent theme of plotting and discussion, though the only one who actually gets abducted is a bit past her prime and formidable in defense of her virtue. The ghosts are a colorful lot and rather impulsive but, in the long run, willing to listen to reason. In fact, when you look at the story carefully, the one who commits repeated betrayals is an honest, open British sailor who always listens to what his heart tells him.

The quality of the evening became apparent before anyone appeared on stage. It could be seen in the imaginatively designed proscenium, looking like a stone arch in a Renaissance castle, adorned with carved figures of dragons and knights in armor. Or in the scrim, which was adorned with figures of mythical beasts whose eyes glowed red in the dark. Or the small, ornately Victorian screen that was lowered during the overture to project the credits for this "New and Original Supernatural Opera."

All these visuals are the work of designer Zack Brown, who had the audience laughing heartily before a single syllable had been spoken or sung. In a special way, this is Brown's "Ruddigore." It was originally intended to be Edward Gorey's, but that reclusive genius withdrew and Brown was substituted. Gorey is a hard act to replace, but Brown did it triumphantly, reveling in his own eclectic array of styles while daring to hint occasionally at Gorey's distinctive mannerisms.

Brown's contribution to the production, merging harmoniously with that of stage director Peter Mark Schifter and choreographer Michael Phillips, made this a "Ruddigore" that could be enjoyed even by the tone-deaf. Visually, it reached its peak in Act 2, when the ancestral portraits of all the bad baronets of Ruddigore step out of their picture frames. Amid the great, spooky chorus, "When the night wind howls," the scene shifts to a graveyard and the Murgatroyd ancestors are joined by miscellaneous other ghosts, including one with an ax protruding from his skull and another who carries his severed head cradled in his arms. The effect is chilling, but also oddly funny, when this detached head starts speaking. This scene is the company's most striking visual use of a chorus since the final scene of "The Rake's Progress" several years ago.

Still, the words and music are the primary attractions. Musically, Randolph Mauldin conducts a beautifully styled, superbly balanced interpretation with no moments of serious weakness. In the verbal department, one knows that this "Ruddigore" is on the right track by the third syllable of the opening chorus, sung by "an endowed corps of professional bridesmaids." The chorus is "Fair is Rose ..." and the "O" in that third word is shaped so perfectly that one breathes a sigh of relief and relaxes to enjoy the rest of the show. That "O" has wit and point; it is completely in character and perfectly controlled; it has in microcosm that sense of style and awareness of tradition that are necessary for greatness in any Gilbert and Sullivan production, but it reflects freedom and individuality in the exercise of these qualities.

The promise implied in that "O" is fulfilled throughout the evening -- by everyone on stage but in a special way by Elaine Bonazzi (Dame Hannah), Sheryl Woods (Rose Maybud) and Judith Christin (Mad Margaret) among the women, by Thomas Goerz (Sir Ruthven Murgatroyd), Alan Held (Old Adam Goodheart), Paul Austin Kelly (Richard Dauntless), William Parcher (Sir Despard Murgatroyd) and William Wildermann (Sir Roderic Murgatroyd) among the men. Comparisons are invidious -- particularly in an ensemble effort like this, when each performer makes a unique contribution -- but the most polished and funniest performance of the evening was probably that of Christin and Parcher in "I was once an exceedingly odd young lady." It was perfectly controlled (indeed, control was its primary theme) down to the most imperceptible twitch of an eyelid. Every little movement had at least two or three little meanings all its own.