A man walks into a talent agent's office and tells him he's got the greatest act ever seen. It's a family act: mom, dad, two kids and a dog.

So begins what has often been referred to as the dirtiest joke ever told. From the days of vaudeville to today's comedy clubs, the joke has been passed down from one comedian to another, with each comedian inventing the acts that are performed. When the group is finished, the agent asks, "What do you call this act?" "THE ARISTOCRATS!"

It's very hard to tell a joke. In "My Favorite Year," Mark Linn-Baker tells Jessica Harper a joke beginning with the line, "A man walks into a bar with a duck on his head." When he asks her to repeat it, she says, "A man walks into a bar wearing a duck!" Pretty big difference. As hard as it is to imagine, "The Aristocrats" is comedy's answer to such films as "Lust for Life" and "The Agony and the Ecstasy." And while very few of the almost 100 comedians featured will attain the fame of Michelangelo or Vincent Van Gogh, they are truly artists, working on a canvas of words. The fact that most of the words are of the four letter variety doesn't matter. Each artist approaches the joke like a blank slate and sets about adding their own colorful touches. What begins as a few lines often stretches out for several minutes, with one comedian swearing that he drew the story line out for more then two hours! And it is the story that comes before the punchline that makes the joke funny. As the comedians on screen discuss when and how they first heard it, each one does his best to out shock the other. Many of them use sex as a way to get laughs. More turn to more scatalogical humor. Others do both. Some find it hilarious, others don't understand it. One scene has Tommy Smothers (who knows the joke) telling it to his brother, Dick, who doesn't. Straight man or not, it's great to see Dickie's face as Tommy goes on and on in describing the act. The most enjoyable parts of the film are when the story tellers add something different to the joke. One comedian makes the family Amish. Carrie Fisher tells it using her real folks (Debbie Reynolds and Eddie Fisher) as the parents. One comedian tells the joke using only playing cards while another does the routine entirely in mime! They even channel other entertainers to tell the joke. Mario Cantone tells it as Liza Minelli while Kevin Pollack is hilarious recounting it as Christopher Walken. Even "South Park's" Eric Cartman gets into the act, though none of the boys, Cartman included, seem to get it. Ironically, the raunchiest version comes from "Full House's" Danny Tanner himself, Bob Saget. Believe me, this is one story he won't be repeating to Mary Kate and Ashley! My personal favorites were Gilbert Gottlieb and Taylor Negron. Not so much for what they said but by how they said it.

A warning - the language here is pretty rough. Even though the screening audience I was in knew what the film was about in advance, a few people did walk out. However, if you want to see what makes Billy Connolly, Andy Dick, Whoopi Goldberg, Bill Maher, Larry Miller, Chris Rock, Sarah Silverman and 90 other comedians so funny, this is definitely the film to see. On a scale of zero to four, I give "The Aristocrats"