The evening was already in full swing by the time Jody and Brenda-Lee Prescott arrived at the Beaux Arts Masquerade ball at the Corcoran Gallery of Art Saturday night. Unintimidated by princes, punks, aliens and an abundance of black ties, the pair shuffled to the dance -- a couple of traveling Ionic columns, unwieldy capitals spanning their shoulders.

"We're late because we had to finish them," said Brenda-Lee, a second-year student at the Corcoran School of Art, to which proceeds of the evening's gala will go. About 500 people paid $40 each to support the school's scholarship fund and enjoy an enchanted evening of mystery and dress-up.

Depending on how the crowd shifted, you could stand one minute between a red-caped cardinal and a pitchfork-wielding Devil, the next minute beside a furry-headed cat in tuxedo and eyeglasses. Part-time student John Dunnan wore the requisite gorilla suit. Masquerade patron Pat Lore carried a ball and chain as "Les Mise'rables' " Jean Valjean; her husband Ken was equally theatrical as the Phantom of the Opera.

Some, like Tom Ede and Avis Black, resplendent in red velvet as King Henry VIII and Anne Boleyn, took the costume rental route. Others, like designers Roger and Ann Williams, as Andy Warhol and his easel (she wore Warhol's Marilyn Monroe poster), ransacked their own brains and closets for ideas and materials.

White-bearded and rotund Angus Olson owns his own Santa suit, but he made the finals of the costume judging as a robed monk. "Or maybe I'm Obi-Wan Kenobi," he said, twinkling. One tall, wigged man wore a short French maid's outfit, with bright red tights and high heels, and carried a red feather duster. He would not reveal his name.

The gala, which featured music by a group called the Floating Opera, ended a seven-year hiatus in a long-popular and flamboyant Washington tradition. Corcoran students had set a stage to rival those of past balls by hanging giant silver, gold and black eye masks from the ceiling, and almost every guest, whether in simple mask or silver body paint, seemed caught up in the Beaux Arts spirit.

One of the school's graduates, Joe Lewis, made armor of pop tops for the 1980 gala. This year he earned special notice from the costume judges for his ornate, hand-beaded Egyptian tunic and plumed headdress. "I watched 'The Ten Commandments' on TV and tried to emulate Charlton Heston's outfit," he said. That was nearly a year ago; the chest piece alone took eight months to complete. "You ought to see what I've started for Halloween," said the computer graphics specialist for the Pentagon. What is it? "Oh, it's a secret, but it's even better than this."

Award winners included Corcoran graphics student Charles Cote for his Medusa-like mask of snakes; Patty and Rich Linden, who dressed all in black with traffic-clogged highways climbing their bodies ("Our son wants his cars back"); frame-faced student Christian Wicha; and a trio of enormous flowers. Dave Abbot, a doctor, made the petals for his wife Lynn and Judy Skillman with the tubes of cotton cast lining he uses to set patients' broken bones. "I think I'm a daisy," he said.

But the prize for overall best costume went easily to Brian Ford of Arlington, a designer of air conditioning and heating systems. Ford wore the silver, accordion-like tubes he installs in buildings: One enormous tube started at his ankles and curved out around his face; smaller tubes wrapped around his arms and legs.

"Warm? Of course it's warm," he said. "They're heating ducts!"