The appeal is irresistible -- a genuine flea circus on 42nd Street. Has time spiraled in reverse? Maybe. We venture into the Palace of Variety and take in the cluttered lobby. Prominently displayed is the sturdy stool that once supported Helen Melon, the fat lady of Coney Island. 

''She's so big and so fat that it takes four men to hug her and a boxcar to lug her,'' a sign proclaims.
We plunk down $4, and within minutes are listening to Professor Adam Gertsacov, every bit the fantastical impresario, in his purple top hat and cash-register voice, introducing us to the wondrous insects itching (sorry) to perform. Yes, they can pull objects more than 100,000 times their weight, and, yes, Shakespeare wrote his most famous line about the species: ''To flea or not to flea.'' 

Midge and Madge are the stars of the Acme Miniature Circus of Performing Fleas: they pull chariots, walk the high wire and, truth to tell, are visible only through the magnifying glass Professor Gertsacov uses to move them about with tweezers. The finale comes when he puts the fleas in a cannon and blasts them through a ring of fire. 

Were there really fleas? Maybe, maybe not. What surely existed was a high-spirited glance back at an entertainment form that had been dead as a doornail on 42nd Street since Professor Hecker's Show at Hubert's Dime Museum closed in 1957. It is part of a revival of old-time show business in New York City -- with plenty of echoes nationally -- that includes vaudeville, burlesque, sideshow, baggy-pants comedy and the circus arts, all with more than a dash of the urban self-consciousness associated with performance artists. 

The old has become new. For the first time in 70 years, there is a continuous vaudeville show in Times Square, the Bindlestiff Family Cirkus. It appears in the same space as the flea circus, showcasing in one recent performance an old-fashioned ukulele duo, a yo-yo master, a trapeze artist, a whip act, a sword swallower. But the new edginess is evident in the yo-yo guy doing hilariously risqué tricks, and the trapeze lady ending the evening with a spectacular airborne striptease.

It is sometimes called the New Vaudeville, though nobody seems to relish the moniker. (Penn & Teller, the magicians for the thoughtful and accused of being New Vaudevillians more than a decade ago, despise the term.) What could be new about acts as ancient as jugglers brilliant at bumbling?
The answer is attitude. Today's performers are clearly younger, the intellectual riffs on seemingly old-fashioned acts are green-apple fresh and, in some instances, shows are longer, deeper and more thoughtful.

Todd Robbins, a magician and sideshow performer who has just started a new variety show in SoHo, says why not call it Newer Vaudeville. Trav S.D. (Get it? Travesty), who has his own vaudeville show starting Dec. 13, said vaudeville's turn-of-the-century pioneers were immigrants a step removed from Ellis Island. They worked the boards because it beat working in factories.
''Instinctively, we're artists,'' he said of the new generation.
Some call the new scene postmodern vaudeville, a term that makes others groan. ''Postmodern is so last century,'' said James Taylor, publisher of Shocked and Amazed magazine, which is devoted to the sideshow arts.
Dick Zigun, whose Coney Island U.S.A. has pioneered the resurrection of old entertainment forms in New York City since he established a beachhead in Coney Island in 1985, thinks neo-geo-vaudeville might be just the term. He has no idea why.
Katherine Valentine, who put together Va Va Voom Room, a traveling troupe of actors who combine old striptease routines, juggling and humor with a performance-art sensibility, says it all comes down to the Big Wow.
''You've got to have a gimmick,'' she said. ''A really brilliant gimmick.''
The Bindlestiff lineup changes at least every weekend. And the acts change much faster. Mr. Pennygaff, sword swallower extraordinaire, began a recent show by announcing that anybody who didn't like him could wait six minutes and see something completely different. And sure enough, the Fire Goddess materialized. There was a cotton-candy evanescence to things.
''This combination of performers may never be seen on the same stage again,'' intoned Mr. Pennygaff, who in reality is Keith Nelson, one of the founders of Bindlestiff. You know the type: he cuddled an Emmett Kelly doll as a child, traded a bottle of whiskey for juggling lessons and majored in anarchist studies at Hampshire College.
His partner is Stephanie Monseau (Ringmistress Philomena), who started out as a modern dancer. The two met a decade ago when both were waiting on tables in the East Village, and have since toured hundreds of thousands of miles doing everything from rope tricks to eating light bulbs to distributing esoteric left-wing literature. As the enjoy-yourself-or-else mistress of ceremonies, Ms. Monseau has cultivated a sneer as she snaps a bullwhip to bisect the cigar protruding from a trembling Mr. Nelson's fanny.
''We're not using our vaudeville skills to turn theater into circus,'' she said, ''but to enhance the theater experience.''
There are plenty of vaudeville experiences right in the Palace of Variety, part of the four-storefront Chashama arts complex that the real estate mogul Douglas Durst has lent his daughter Anita, an avant-garde arts producer. She likes vaudeville because she thinks its conventions demand more thought than free-form performance art, and it's cheap.
''Everybody is able to experiment without too much at stake,'' she said. ''They can make mistakes and it's not like they're going to lose thousands of dollars.''
People don't do stuff for money anyway. Take the guy who comes to the 11 p.m. amateur night at the Palace of Variety and exhibits his talent. He lies down so that female audience members can run a vacuum cleaner over him. If a male tries, he barks: ''No! That's weird.''
Other acts appear weekly, including the Kourageous Kipplengers, who come on like a frumpy middle-aged couple but play mean kazoos. Like other headliners, they bring accomplices. An act promised by Trav S.D. in his American Vaudeville Theater is Trixie's All Girl Chorus.
It's old-fashioned variety entertainment of the sort Ed Sullivan so astutely scooped up, but with twists. So what would you expect from these guys? Trav, who never uses a two-syllable word when five will suffice, said he started in show business as part of a trained cat act. He was too big for the suit and couldn't keep up with the other cats, so he became a swordfish swallower. He worked without a net.
If you don't believe that, you might take in Todd Robbins's ''Sideshow Saturday Night'' at the SoHo Playhouse. Appearing in some shows will be Lizard Man, who is dedicated to turning himself into a lizard. Already, he has green scales tattooed on every square inch of his body and a tongue split with a laser. The implants above his eyes make him look like an iguana.
''When you do something real that people think is impossible, they can't deny what they're seeing,'' Mr. Robbins said. ''They start to wonder how these things are possible and that means they're thinking.''
Thinking is what ''Clown Brain'' at the Flea Theater in TriBeCa is all about. Dick Monday, leader of the New York Goofs, a clown group, works with a psychotherapist to pursue his nagging existential question: why is he happier as a clown than without makeup? (Mr. Monday just turned 50 and has taught clown skills to the younger generation of vaudevillians, who are almost all under 40.) His quest is interrupted by old-fashioned vaudeville bits, like Mr. Monday playing ''Moon River'' on a saw. When he plays the piano, a key falls off. ''That always happens when I get keyed up,'' he intones.
A psychotherapist in the audience says the answer to Mr. Monday's question, arrived at rather torturously in the play, is obvious. ''It's about fun, connecting to basic stuff,'' Martha Rose said. ''Laughter.''
THAT'S sure true of ''Happy Hour,'' in which three 20-something clowns jump on trampolines and carry whoopee-cushion humor farther than you might imagine. Events crescendo haphazardly to the oddest climax: a performer in rabbit ears hops from lap to lap in the audience.
''The audience doesn't know whether to cry, laugh or throw up,'' said Matthew Morgan, the bunny.
Vaudeville had its origins in beer halls, and its first audiences were immigrants seeking refuge from tenements and factories. Andrew Davis, who wrote his doctoral dissertation at New York University on burlesque comedy in 2000, likens the present time to the period when the vaudeville arts were young and sparkling, a few years before they became the staple of theater chains.

''There's a lot of exploration and nobody's quite sure where it's going,'' he said. He thinks the ultimate synthesis will involve an unpredictable cocktail of vaudeville, burlesque, circus, sideshow and, as is happening, particularly in Los Angeles, elements of the dance club scene. Increasingly, new immigrants, as yet not much involved, will provide impetus in spirit, he thinks. His hope is that cable television does not jump on the new variety and wring out its vitality, as it has with stand-up comedy.

It isn't going backward, but the occasional glance through the rear-view mirror seems inescapable. For example, a new show at the Palace of Variety does take on the routines of Chaplin and Keaton.
Called ''The Golden Age,'' it is the brainchild of Joel Jeske. He dedicated himself to revivifying old-time variety when he was shocked (yes, shocked) at the news that Universal Studios was removing the characters of Chaplin and Laurel and Hardy from its theme parks. Few recognized them.
Mr. Jeske's conversion to premeditated zaniness happened in his native Chicago when Professor Inferno taught him his legendary act: holding his hand over various candle flames. The performer then screams at different pitches to create incendiary tunes like ''My Old Flame.''

But what is the New Vaudeville without the New Burlesque? Better clothed, for sure. From San Francisco to New Orleans to SoHo, women have taken the classic striptease numbers and remade them in imaginative, often feminist modes. Men, too, actually: theproductions are equal-opportunity exposers.

Still, the shows are more than nudity, and the nudity itself challenges contemporary body stereotypes. At the East Village club Fez, Va Va Voom Room, a new burlesque revue, was appearing the other night. Two of the most creative strippers were delightfully zaftig: one called herself Bob and wiggled out of a cowgirl outfit. The other, Dirty Martini, stripped on pointe in a costume of balloons, popping them with a cigarette.

Interspersed with the strippers -- among them a man who hilariously and acrobatically stripped in female drag -- were acts ranging from magicians to a beatnik-style French lounge singer who became so depressed by his act that he finally simulated suicide. There was also ample audience participation, a hallmark of the new variety: birthday celebrants were called to the stage to experience the ''spanking machine.''

It all harked back to ''Lydia Thompson's British Blondes,'' the show that introduced burlesque to the United States in 1865. It consisted of three parts: songs and coarse sketches; baggy-pants comics along with acrobats and magicians, and a finale featuring an exotic dancer or a boxing match. Not until Little Egypt introduced belly-dancing at the World's Columbian Exposition in Chicago in 1893 did the striptease become standard burlesque fare.

Things progressed. Come 1933, Sally Rand at another event in Chicago, a Century of Progress International Exposition, introduced the fan dance. As near as anyone can tell, Dirty Martini does a perfect imitation. The old has become new. Life is grand.

''So step right up, folks!'' the barker barks. ''Witness the historic and triumphant return of the flea circus to Times Square. It's only $4, but we'll take $8. And, yes, ladies and gentlemen, the creatures perform naked.'' 

Shows on the Side
New York's current vaudeville revival is centered at the Palace of Variety, at the Chashama arts complex, 125 West 42nd Street, where these shows are now running or are about to open: Bindlestiffs, the Golden Age, Acme Miniature Circus of Performing Fleas, Kourageous Kipplengers and American Vaudeville Theater. All can be reached at 1-877-BINDLES or or

And in other Manhattan theaters:
* Va Va Voom Room: 212-330-9349 or
* Happy Hour: 212-631-5819 or or
* Sideshow Saturday Night With Todd Robbins and Friends: 212-615-6432 or
* Clown Brain: 212-206-1515 or or
Photos: Joel Jeske, left, screaming in tune at the Palace of Variety; Mr. Pennygaff of the Bindlestiff Family Cirkus, center, with ''sword''; and Dirty Martini popping her balloons at Fez. (Richard Termine for The New York Times); (Tom Tavee); (Richard Termine for The New York Times)(pg. 5); Mark Gindick, top, Ambrose Martos, left, and Matthew Morgan in ''Happy Hour.'' (Richard Termine for The New York Times)(pg. 6)