Video: 'Never Before, Never Again: Behind-The-Scenes Of Asssscat'

The folks at Upright Citizens Brigade recently allowed a camera to film a behind-the-scenes look at their famous Asssscat show that has been running for 15 years in New York City and Los Angeles. The free show runs on Saturday and Sunday nights, depending on the city, and people wait in line for hours to try to get in and catch a glimpse of their favorite comedians in these one-time gigs that are never, ever repeated.

UCB, of course, started in Chicago in 1990 with a lineup that featured comedians Matt Besser, Ian Roberts, Adam McKay and Horatio Sanz, among others, but it is most commonly associated with Amy Poehler, as the sketch group hit Comedy Central for an Upright Citizens Brigade series on Comedy Central from 1998-2000.

But the fun of Asssscat is that any number of popular comedians and actors can show up on any random night and be a part of the show, as the video reveals people like Jon Hamm, Nick Offerman, Janeane Garofalo and Jason Mantzoukas, among others, stopping by to produce some belly laughs.