The Gilbert and Sullivan Players' Sorcerer has powerful magic. Depending on whether they believed their tickets or their programs, at 8:00 or 8:30 in trooped the opening-nightdress: grim. Two hours later they streamed out: smiling. The G & S Sorcerer cast a spell on them, from the start: "Forget your notes of mournful lay," the chorus commanded, "and from your throats pour joy today." All obeyed.

In the garden of Sir Marmaduke's Elizabethan Mansion all manner of delights transpire. But though Sir Marmaduke, an elderly baronet, may rule the mansion, his neighbors reign over the garden. Everyone, who does not pine after anyone, pines after someone in particular.

Chief to the love-loran, and a joy every minute she is on stage, is Constancy (Melanie Adams), who yearns unrequited for Dr. Daly (Joel Martin), Vicar of Ploverleigh. Constancy and Dr. Daly very nearly dominate the entire evening and to no ill effect. Miss Adams has plenty of ham and an admirable voice, she can leer lasciviously and make a mock-tragic aria sound like decent Mozart. Joel Martin sang more clearly and yet with more spirit than most people speak.

While Constancy's mother (Miranda Samples) attempts to connect her love-sick daughter with Dr. Daly, one love approaches fulfillment: Alexis (H. Thomas Bell), son of Sir Marmaduke, will soon wed Alien (Carolyn W. Kimball). But Alexis, cursed with ideas, thinks indiscriminate and widespread marriage will bring all earthly joys and accordingly engages a respectable family sorcerer (Peter Skolnik) to enamour the villagers of each other. The results are lively Gilbert and Sullivan.

If the operetta rested on Alien, Alexis, and the sorcerer (it doesn't, so don't worry), it would have only one really strong leg. Miss Kimball sports a magnificent red wing and a voice to match; her eyes and other accoutrements rove interestingly. She, like Constancy and Dr. Daly, is fun to watch and hear. Alexis, unfortunately, cannot sing, but he overcomes this handicap in the wisest way: by singing loudly and acting well.

The sorcerer, J. Wellington Wells, fails to be terrifying enough; he is much too amiable. In preparing the love philter, for example, he innocents in the tone in which one normally makes introductions; at the end (I must not disclose the end), he sounds as if he were going on vacation. Otherwise, Mr. Skolnik is splendid. His patter is palpitating, his dancing delightful.

The support of the central cast never waned. Lady Sangazure (Susan Bly), Sir Marmaduke (Lucian Russell), the Counsel (Philip Hartman), the Page (Jeffrey Cobb), and the chorus all added fine moments to the show. But here I suspect much of the genius - and there are bits of action that are genius - rests largely with the stage director, David Mills. If he is responsible for the choreography of the chorus, he deserves congratulations; if he created the gestures, the Victorian self-mockery, the hands that reach out of the curtain so that things conveniently disappear, he merits awe.

Complementing Mills' direction were the music conducted by Thomas Walker, the costumes of Lewis Smith, and the scenery of John Friedman. The costumes were particularly brilliant, the scenery cleverly attractive. Mr. Walker's orchestra was surprisingly facile given the limitations of its size, and nearly everywhere balanced the voices properly. Hopefully, some raggedness in the finale of the first act will disappear in the performances to come.

Still, in a Cambridge world, the G & S Sorcerer is a gift from another time and place, a gift worth taking with relish.