Urban legends die hard, but few are more enduring than an age-old debate about one very particular episode of The Simpsons. That debate involves a psychiatric hospital, an uncredited role and the King of Pop himself, Michael Jackson.

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The years-old debate stretches all the way back to the 1991 Simpsons episode “Stark Raving Dad,” which sees Homer committed to a psychiatric hospital. While receiving treatment in the hospital, Homer meets a man who is very clearly not Michael Jackson but claims to be. While the character sounds exactly like Michael Jackson, the role was credited to John Jay Smith (an obvious alias).

Fans have wondered for years if the voice actor was, in fact, Jackson himself. Now, Simpsons creator Matt Groening has revealed that the part really was Jackson, but the story doesn’t end there. That’s because the episode also includes a song called “Happy Birthday Lisa” that is sung by the character.

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It would be natural to assume that Jackson would do the singing for the part, too. That’s not the case, though. Instead, a singing double had to be brought in due to Jackson’s deal with his record label. That singer then had to perform in front of the King of Pop himself -- while imitating him.

Now, that’s a story to tell the grandkids.