But one celebrity appearance has always been shrouded in mystery: Michael Jackson.
In the 1991 episode ‘Stark Raving Dad’, a guy called Leon Kompowsky pretends to be the King of Pop and helps Bart find the best birthday present ever for Lisa.
The episode culminates in the immortal rendition of ‘Happy birthday, Lisa,’ which has got to be one of the finest songs in the history of The Simpsons.
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But, curiously, MJ was never officially acknowledged and the voice was credited to John Jay Smith, leaving many wondering whether Jackson performed the speaking part, the singing section, or both – or neither.
And Matt Groening has now addressed the confusion around that famous cameo and how it all came about.
While speaking with The Weekly, Groening said: “We really did have him.”
“I was sitting in the office late at night, the phone rings and I pick it up,” he added. When the voice on the other end said “Hi, this is Michael Jackson,” Groening at first didn’t believe him because the singer has “a voice that sounds like somebody doing a Michael Jackson bit”.
Jackson immediately called back and insisted that it really was him, and “he said that he loved Bart and wanted to be on the show.”
But why the confusion around MJ’s involvement?
“He didn’t want credit for it, or there was some kind of deal with his record company or whatever, so when it came time to sing the songs, he had a sound-a-like singer,” Groening explained. “He stood there and watched the guy, who was so nervous, who had to sound like Michael Jackson, and then he giggled.”
What a wonderfully weird story. We wouldn’t expect anything less from the King of Pop.