There aren’t supposed to be mistakes on Jeopardy! It’s the “smart” game show. Save that sh*t for Wheel of Fortune. But on Wednesday, the game show made a rare error.

The category was “Real Names of Unreal People.” The clue for $600: “Robert Underdunk Terwilliger is the real name of this vengeful The Simpsons character.” Troy Meyer, a music executive from Tampa, Florida, correctly guessed Sideshow Bob, but Jeopardy! had the incorrect name for the H.M.S. Pinafore-loving, Bart-murdering (non-canonical), dam-building villain.