The U.S. version of the British improvisational-comedy showcase features a panel of talented performers who wing it unscripted and unrehearsed. It's "comedy without a net," according to executive producer Dan Patterson, as the group participates in audience-suggested skits, games, song parodies and other bits. The U.K. version aired on Comedy Central from 1990 to '97. The initial U.S. incarnation ran on ABC from 1998-2007.