The Five Main Reasons Celebrities Agree To Guest Star On The Simpsons

There's a long, complicated history of celebrity guest stars on "The Simpsons," especially in those early seasons where the celebrities were often never officially credited for their roles. Sometimes the celebrity fits into the "Simpsons" universe perfectly, and sometimes they stick out like a sore thumb. Sometimes they play themselves, and sometimes they play a brand new character. Sometimes they're revered by the characters, sometimes they're treated with total contempt. There are no rules here, although, after 35 seasons and counting, we've learned to pick up on some trends.

In "Simpsons" writer Mike Reiss' 2018 behind-the-scenes book, "Springfield Confidential," he wrote a bit about why so many celebrities have chosen to appear on the show. "The Simpsons" has made it into the Guinness Book of World Records for its absurd number of guest stars, and Reiss has argued that most of them came on the show for one of five reasons.

"Even a leading guest role doesn't take more than an hour to record, and there's no wardrobe or makeup to worry about," Reiss explained. "Plus, the celebrity can come in at his or her convenience, anytime during a two-month window. Or not come in at all — we've recorded guest stars in their homes, in their cars, and over the phone."

This is what happened with Julian Assange, the controversial Australian WikiLeaks founder who was incarcerated for violating the Espionage Act in April 2019 and who dealt with major legal troubles long before that. Back around 2012, Assange found time to record a few lines for the season 23 episode, "At Long Last Leave." Assange plays the Simpsons' new weird neighbor; some of his line readings might sound a little off, and that's because Assange was recording it over the phone. He was trapped in an Ecuadorian embassy in London at the time, so recording on set wasn't an option for him.

With most guest stars, the situation isn't usually so dramatic. Dustin Hoffman in season 2 simply stayed in New York to record his lines, because it was more convenient than flying to Los Angeles. Likewise, when former British Prime Minister Tony Blair cameoed on the show, he also recorded his lines from London. The rule seems to be that the farther away the guest star is from Hollywood, the more likely they'll be staying home.

"The reason we had so few older guest stars on the early episodes is because senior citizens never watched our show," Reiss explained. "For one episode, we offered the role of God to Burt Lancaster, Charlton Heston, and Gregory Peck, who all said no. Years later, Kirk Douglas appeared on our show as a con man. He had a stroke shortly after, making the Simpsons role his last lusty, full-throated Kirk Douglas performance."

This reasoning is no surprise to a lot of long-term "Simpsons" fans, as a lot of the older guest stars we did get in the early seasons were famously a little difficult. Season 7's standout "Marge Be Not Proud," for instance, featured a gruff performance by the late Laurence Tierney. Described by showrunner Josh Weinstein as "the craziest guest star experience we ever had," Tierney famously did not understand the humor behind the scene where his character leaves a message to the Simpson landline, forcing the writers to make up some fake dialogue for him to respond to instead.

But as the show gained more and more popularity (and as so many modern celebrities grew up loving the show), most guest stars today are genuinely happy and excited to be there. For example, the boy band *NSYNC was clearly having a blast making the 2001 episode "New Kids on the Blecch," to the point where the show even showed footage of them behind the scenes throughout the end credits. 

"No explanation needed here," Reiss said about the third rule. For the fourth one regarding the grandkids, he added, "This was the case with George Harrison, and it made us all feel very old." The Beatles' guitarist Harrison showed up briefly in the 1993 episode "Homer's Barbershop Quartet," playing himself at an awards ceremony, although he was hardly the only musician to join "The Simpsons" for his family. Sting, for example, also recorded some lines for the 1991 episode "Radio Bart." He did so specifically because, in his words at the time, "My kids told me I should do this. They watch 'The Simpsons' all the time ... so I took their advice."

Likewise, Meryl Streep voiced Jessica Lovejoy in 1994's "Bart's Girlfriend" at least partially because her kids wanted to. Bart's voice actress Nancy Cartwright once told the Chicago Tribune about her experience working with Streep for the episode: "She taps me on the shoulder and tells me she's got a 14-year-old at home who loves the show and could I sign an autograph? It was one of the highlights of my career: Meryl Streep asking for my autograph."

Strangely, the opposite dynamic happened with season 3's "Homer at the Bat." There, baseball star Ken Griffey Jr. was hesitant about the lines written for him, but it was his father Ken Griffey Sr. who encouraged him along. As the seasons go on and the show's golden years still tower over the rest, it's probably grown more common for young celebrities to be egged on by their parents, not the other way around.

"Jim Brooks has brought in as guest stars half the cast of his old series 'The Mary Tyler Moore Show': Cloris Leachman, Ed Asner, Betty White, and Valerie Harper," Reiss explained. "Jay Kogen delivered his friends Phil Hartman and Jon Lovitz from the comedy troupe 'The Groundlings.' Sam Simon drew on his days at 'Cheers' to cast Kelsey Grammer as Sideshow Bob."

Although so many of the "Simpsons" writers in the early seasons seemed (in hindsight at least) so young and early into their careers, it's a good thing that a lot of the creatives were still established enough in the industry. Would we have been able to enjoy the magic of Sideshow Bob if Sam Simon hadn't worked on "Cheers," letting him reel in such a big name to join "The Simpsons" in its first-ever season before anyone could guarantee the show would be a major hit? Probably not, and for that we're thankful for good old-fashioned networking. 

Of course, Reiss didn't mention the most important reason of all why a celebrity would stop by "The Simpsons," which is that sometimes the show had just the perfect role in store for them. Especially in the show's golden age, there've been countless occasions where the celebrity's acting blended seamlessly with the show's vibe. Albert Brooks as Hank Scorpio, Johnny Cash as a talking coyote, and John Waters as John in "Homer's Phobia," all gave a performance that would've been revered even if nobody knew who they were. The circumstances behind each "Simpsons" guest star vary a lot, but when the writing is at its best, the results are always worth watching.