The Permanent Change Paul McCartney Made To The Simpsons

It's difficult to fathom, but "The Simpsons" has been on the air for more than three decades, and currently holds the title of longest-running scripted primetime series in the history of television (via USA Today). It was even named the Best TV Show of the 20th Century in a 1999 Time Magazine piece. And that's a seriously impressive feat for an animated program that actually got its start as a series of shorts that played on a long-since canceled sketch comedy series.

As it is, "The Simpsons" is now airing its 33rd run of episodes on Fox, and currently has over 700 episodes under its belt. And among the many other impressive feats "The Simpsons" has accomplished over the years, the series is almost certainly leading the television landscape in terms of super famous guest stars. In fact, turning up on an episode of "The Simpsons" has become a sort of right of passage for actors and musicians from every generation — even for those who hardly need the exposure.

And if there were ever a celebrity that didn't need the exposure a guest spot on "The Simpsons" promised, it was rock & roll icon Sir Paul McCartney. That didn't stop the former Beatle from appearing on the show anyway way back in a beloved Season 7 episode. Turns out, however, McCartney's appearance on "The Simpson" came with a catch — one that permanently changed an aspect of a key character. 

That character was, of course, Lisa Simpson, who forever swore off eating meat in the Season 7 episode titled "Lisa the Vegetarian." She did so with a little help from Sir Paul McCartney, whom she ran into late in the episode, only to discover that he's a vegetarian himself. As McCartney confirmed in a sprawling 2020 interview with GQ, he played an integral role in ensuring Lisa's transition to vegetarianism was of the permanent sort. McCartney told the publication, "We were a bit worried that she would be a vegetarian for a week, then Homer would persuade her to eat a hot dog. The producers of the program assured us that she would remain that way and they kept their word."

That fact was actually confirmed in 2020 by long-time "The Simpsons" show consultant David Mirkin who, as covered by CosmicMagazine, told Radio Times magazine that "[McCartney] agreed but made me promise to keep Lisa as a vegetarian." Per Mirkin, he was "happy to comply" because he's a vegetarian too. Nonetheless, Mirkin claims McCartney has remained vigilant in checking up on Lisa's vegetarian status whenever they see each other in public, stating, "He always checks. And he's always surrounded by nine or 10 lawyers, so it's quite frightening." Given that McCartney's appearance was in 1995, that fact could not be more impressive.