The Aristocrats is the documentary that reportedly had people rolling in the aisles at last year's Sundance Film Festival. Made by a couple of stand up comedians (Paul Provenza and the Penn Jillette, the Penn half of magic-busting TV duo Penn & Teller), it goes back stage to reveal one of vaudeville's filthiest jokes, secretly handed down through the generations. The technique behind this film is simple: take a DV camera, a hundred comedians between gigs, and one of the filthiest jokes imaginable and hey presto! The Aristocrats the documentary is born, so named after the punch line of said taboo joke. Provenza and Teller lob in on their funny man - and lady - friends to investigate a gag that makes people do just that. It includes just about every transgression known to man ' bestiality, incest, scatologogy and more. A who's who of American and British comics get in on the act, telling and re-telling the joke like there's no tomorrow, including Phyllis Diller, Eric Idle, Whoopi Goldberg, Robin Williams, Sarah Silverman, Jon Stewart, Billy Connolly and the cartoon kids from South Park. Twenty minutes into The Aristocrats I began wondering how it would make it to ninety, as the joke and many of the celebrity performers had already worn out their welcome. The biggest problem is the poor editing, as most of the good material was used up too early, possibly due to the inexperience of these two first-time filmmakers, clearly overwhelmed by the hundreds of hours of material they had recorded. Over-analysing the joke didn't help either as it kind of killed the humour ' it really was done to death, with not all of the improv or performances successful in execution. In the right hands films about comedians and the comedy process can be masterful. Bob Fosse's Lenny (1971) was one such example, striking a perfect balance between profiling the brilliant comedian at hand (Lenny Bruce as played by Dustin Hoffman), while simultaneously spotlighting the cultural role of stand up and deconstructing the comedy process. Disappointingly The Aristocrats comes off more as an in-house training video for comedians and their mates, the calling card of Penn Jillette, who's made a career out of spilling the beans on the secrets of behind magic and magicians. In theory The Aristocrats was a nice idea but the practice leaves a lot to be destired. The Aristocrats still has its moments and plenty of them, repeatedly kicked back into gear by some unpredictable performances. The wonderful Steven Wright brings his usual deadpan invention to the proceedings, Cartman and the kids from South Park make the joke work in a way that only cartoon characters could, and brownie points must go to card sharp Eric Mead and Billy The Mime, who inventively transforms the joke with physical humour. But the trophy for 'most off the wall' must be awarded to Bob Saget, the actor/comedian formerly of saccharine 80s sitcom Full House. In a protracted, unwieldy improv sequence (that puts Robin Williams to shame), Saget revels in taking The Aristocrats all the way and then some, happily sacrificing his family-friendly persona in the process.