Artists Flesh Out Annual Danse Macabre : Halloween: At a Hudson River estate, huge skeletons are jointed and jeweled. They will float through New York, with thousands of free-lance paraders.

It’s an inspiring setting for a group of artists: a 400-acre estate overlooking the Hudson River, crimson leaves cascading to the ground with every breeze, and a 19th-Century mansion sitting in the long shadows and soft light of the low autumn sun.

But these artists are not painting bucolic landscapes in green and gold.

No, they’re creating an altogether different tribute to the season: Halloween skeletons, 15 feet high, with grinning, sequined skulls, gleaming white ribs, and neon pink-and-lime costumes that can withstand the glare of city street lights.

This is the secret workshop behind the annual Greenwich Village Halloween Parade--a procession so freewheeling and fabulous that most spectators don’t realize it’s actually a meticulously planned work of art.

“You can’t do an event for a million people spontaneously, but we really struggle very hard to keep it feeling like that,” said parade director Jeanne Fleming, who lives behind the elegant mansion of this Ulster County estate in a modest, rented cottage.

For a month each fall, a dozen artists descend upon the place to plan the parade and build its larger-than-life puppets.

On Halloween, the props are trucked 100 miles south to Manhattan, where they form the backbone of a spectacle that has 10,000 participants and more than a million onlookers.

About half the marchers are invited guests, including volunteers who carry the puppets, jugglers, stilt-walkers and 40 bands playing mariachi music, Dixieland jazz, bagpipes, you name it.

The rest of the participants--about 5,000 people--simply show up at dusk and join the party. There are drag queens dressed as Carmen Miranda and Marie Antoinette, college roommates disguised as Chinese takeout food and children playing the latest super-hero.

Ben & Jerry came one year disguised as cows. John Moynihan, son of New York’s erudite senator, regularly dresses as Death and brings a few dozen friends to help carry a 25-foot-long dancing snake. “I do this great Grim Reaper cheerleading gag with my scythe,” he said.

Sure, New York has other large parades, but “you don’t have to be Irish or gay to join this one,” said Mark Kindschi, a set designer who helps build the puppets. “You just show up and you’re in it.”

And that, said Fleming, is what gives the parade “its extraordinary feeling of spontaneity. I never know what it will look like. At the same time, there has to be a structure around which all of that can happen, so that when people come they’re not in the middle of chaos.”

This year’s parade takes its theme from Mexico’s Day of the Dead--hence, the skeleton puppets dancing on poles, decorated with butterflies, lizards and tropical flowers. The centerpiece float will be a giant god of destruction and creation with the head of a bird, accompanied by students from a New York University dance class in hoop skirts.

Puppets from past parades also will take part: a spider monkey, a snapping toucan, a giant crab, skeletal fish, flapping bats made from umbrellas and even some friendly penguins from a previous tribute to Antarctica.

The event is known as New York’s Mardi Gras, attracting spectators from around the world and generating millions of dollars in tourism. That’s a pretty good return on Fleming’s $35,000 budget, a mix of private and government funding used for art and office supplies, truck rentals, $50 honorariums for the bands, $1,000 stipends for a half-dozen of the most devoted artists and food for everyone who shows up in Fleming’s kitchen.

The parade was started by Ralph Lee, a Village puppeteer and mask-maker who was inspired by the annual Halloween procession in his hometown of Middlebury, Vt.

Fans of Lee’s puppets had asked him to exhibit his work, but he didn’t want his creations sitting in a stuffy gallery. So, in 1973, he rounded up 100 artists and actors to carry the puppets through the streets on Halloween.

Along the route, he staged mini-dramas--a witches’ dance, ghosts haunting a Bleecker Street fire escape, a battle between Good and Evil on church steps.

Other costumed New Yorkers began to tag along and, within a few years, the parade had hundreds of marchers and thousands of spectators.