Air date: 5/20/1997
Conventional wisdom dictates that the worst way to end a series is with the revelation that the entire thing was a dream (shouts out to St. Elsewhere). Roseanne's finale somehow found an even worse way to call it quits. The final ten minutes of Roseanne reveal, via voice-over narration, that Roseanne "wrote" an alternate reality for herself and then played it out in the psychically damaged television show of her mind.
After years of bawdy, rough-around-the-edges banter, you're left with Roseanne sitting in front of a typewriter, reflecting sadly on feminism and family. Though this last minute narrative shift negated the ridiculous plot point that was the Connor's winning the lottery and all the subsequent shenanigans that marked a rough final season, it's hard to think of a worse ending to a sitcom than melancholy monologuing in a dark basement.