Hayes' resignation came as backlash to South Park's infamous 2005 episode "Trapped in the Closet," in which Tom Cruise is depicted hiding in an actual closet, refusing to get out, and Scientology is meanwhile skewered throughout. In the interview, show creator Matt Stone says that he spoke with Hayes after they finished the episode and it was "pretty obvious from the conversation that somebody had sent him to ask us to pull the episode."
"It had already gone on the air, and we didn't tell him because we didn't want him to be held accountable. Plausible deniability," Hayes continued.
But according to Hayes III, the iconic soul singer did not quit on his own accord while he was incapacitated due to health issues .
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"Isaac Hayes did not quit South Park; someone quit South Park for him," Hayes III told THR. "What happened was that in January 2006 my dad had a stroke and lost the ability to speak. He really didn't have that much comprehension, and he had to relearn to play the piano and a lot of different things. He was in no position to resign under his own knowledge. At the time, everybody around my father was involved in Scientology -- his assistants, the core group of people. So someone quit South Park on Isaac Hayes' behalf. We don't know who."
"My father was not that big of a hypocrite to be part of a show that would constantly poke fun at African-American people, Jewish people, gay people -- and only quit when it comes to Scientology," continued Hayes III. "He wouldn't be that hypocritical."
Stone, to his knowledge, verified the assertion: "We sort of figured out the whole picture a bit later, but that's totally what happened.... It really sucked, the whole thing. This statement put out that he was quitting, it kind of called us bigots."
Trey Parker, Stone's creative partner, added, "But we knew in our hearts there was something way more rotten going on."
Hayes died from a stroke on Aug. 10, 2008. He was 65.
Read THR's full oral history of South Park here.