As one of the most successful and longest-running sitcoms in recent television history, CBS' The Big Bang Theory accomplished some pretty impressive things. As per ScreenRant, it surpassed the iconic sitcom Cheers as the longest-running multi-camera sitcom in television history. It has won countless awards and racked up a truly absurd amount of nominations beyond that, and its starring cast has skyrocketed to A-list fame.
But, it isn't just the main cast of characters that includes some pretty well-known names. Over the course of twelve seasons and 279 episodes, The Big Bang Theory has had an endless parade of celebrities appear in roles of varying significance. Whether science fiction icons, television legends, or real-life scientific geniuses, the guest stars on The Big Bang Theory are nothing short of out of this world.
Updated on August 3rd, 2022 by Tanner Fox: The Big Bang Theory may have concluded in 2019, but it remains one of the most relevant recent sitcom series. Not only did it tap into the pop culture phenomena of Marvel, Star Wars, and all things geeky, but it also intertwined relatable comedy with heartfelt romance and drama in ways that felt authentic and captivating.
A part of the show's appeal stemmed from the many wild cameos and celebrity appearances that were included over its twelve-season run. From James Earl Jones to Steve Wozniak, these are the best of best of The Big Bang Theory.
Bill Nye the Science Guy
You'd be hard-pressed to find any scientist who made a bigger impression on more children than Bill Nye the Science Guy. So, it only made sense that Nye would appear in an episode featuring The Big Bang Theory's equivalent of himself—Arthur Jeffries, also known as TV personality Professor Proton.
Bill Nye's appearance in the series is the result of one of Sheldon's many harebrained schemes for getting revenge for what he feels is a wrong that has been done to him. But, in the end, rather than make friends with a new television icon, Sheldon only winds up with yet another restraining order from a prominent public figure.
Neil deGrasse Tyson
While Sheldon is typically the one to cause trouble, famed astrophysicist Neil deGrasse Tyson was actually roped into The Big Bang Theory canon as a result of a Twitter feud spurred on by Raj. The Caltech physicist hoped to earn some internet clout as a result of the beef, but Tyson quickly settled things by challenging Raj over the phone.
Neil deGrasse Tyson would also be involved in something of a feud between himself and Sheldon Cooper. Sheldon believed Tyson to have played a role in Pluto's demotion from planet status. Still, his best moment in the series came just after he ended his arguments with Raj; after Raj hung up on him, Tyson dialed another number and quipped that there are other scientists who could use a "deGrasse kicking."
Stephen Hawking
Many pop culture icons are introduced into the Big Bang Theory canon as a result of some ridiculous scheme Sheldon cooked up, but very few of these figures can claim to have found themselves in a war of the minds with the starring socially-awkward scientist.
The most significant of these so-called rivals was, without question, the legendary genius Stephen Hawking himself. The back and forth barbs exchanged between the scientific geniuses would span multiple seasons, mostly consisting in the form of exchanged voicemails, though Hawking did appear as himself on multiple occasions. Following his passing in 2018, the series also included a touching tribute to the one-of-a-kind genius.
Carrie Fisher
It wouldn't be a show about real nerds with impressive nerd street cred if they weren't obsessed with Star Wars, Star Trek, or both. The Big Bang Theory gang are, naturally, obsessed with both iconic pieces of science fiction media—among many others—and the series has reflected their very strong opinions by trying to feature as many guest stars from these beloved franchises as possible.
An all too brief but instantly iconic cameo came in the form of the late Princess Leia herself, Carrie Fisher. Fisher appeared at the very end of an episode that found Sheldon embarking on a wild adventure with another of Fisher's own Star Wars castmates, James Earl Jones. Jones and Sheldon attempted to ding dong ditch Fisher's home, leading to her running outside armed with a baseball bat.
Wil Wheaton
Speaking of iconic science fiction stars, Star Trek cast member Wil Wheaton has long recurred on The Big Bang Theory as an over-the-top version of himself who becomes Sheldon's eternal nemesis. Whether they're fighting on dueling bowling teams or waring over who should become television's new Professor Proton, Wil and Sheldon have almost always been at each other's throats.
On a few occasions, it seemed like these two were finally going to be able to let bygones be bygones. But, the rivalry between these polar opposites is one of the best things the series has ever done. Any time Sheldon angrily screams "Wheaton," it's clear things are about to get really good.
Steve Wozniak
One of the co-founders of Apple and the man responsible for many of the company's early technological breakthroughs, Steve Wozniak is a major figure in the world of tech, though he's nowhere near as high-profile as the late Steve Jobs was. Still, that didn't stop Sheldon and company from spotting him dining at the Cheesecake Factory in an episode of The Big Bang Theory.
In the episode, Sheldon begins using a "virtual presence device" in order to preserve his body so that he may one day achieve a sort of immortality. However, he ditches that as soon as Wozniak offers to sign his vintage Apple II, which Sheldon, in his excitement, then drops down a flight of steps.
Laurie Metcalf
It's not just science fiction icons that have popped up on The Big Bang Theory over the years; longtime television and theatre icon Laurie Metcalf had a recurring role on the series from almost the very beginning as Sheldon's old-fashioned mother Mary Cooper.
Sheldon and his mother are almost always at odds in terms of their beliefs and opinions regarding—well, basically everything. But, Mary loves her son more than anything, and she will go to whatever lengths necessary to ensure that he knows this and that he is happy. Their tender relationship is likewise further explored in the prequel series Young Sheldon which finds Metcalf's own daughter, Zoe Perry, taking on the role of Mary.
Levar Burton
While Levar Burton may be best known for his role as Geordi LaForge in Star Trek: The Next Generation, Kunta Kinte in Roots, or even as the host of the beloved series Reading Rainbow, the actor has also made some truly invaluable and hilarious contributions to The Big Bang Theory over the years. None of his guest appearances have been all that long, but, every time he appears on the series, something goes horribly—and hilariously—wrong.
On one occasion, he shows up at Sheldon's apartment after a Twitter invite only to find drunk and half-naked guys singing karaoke. On two other occasions, he appears on Sheldon's Fun with Flags web series only to find himself in increasingly uncomfortable situations due to Sheldon's total obliviousness regarding social protocols. Thankfully, Burton is nothing if not a game comedic performer, and each appearance allows him to make the most amusing facial expressions as a result.
Stan Lee
Sometimes, when people meet their idols, things go exactly as planned. Unfortunately for Sheldon Cooper, nothing ever goes according to his plan. When Sheldon learned that the father of Marvel himself, Stan Lee, was going to be visiting Stuart's comic book shop—and he would be missing out on it—Sheldon was understandably totally beside himself. But, Penny, ever a good friend, managed to do some digging, found out where Stan Lee lived, and brought Sheldon for a visit as a surprise.
As if that weren't creepy enough, Sheldon invites himself into Stan Lee's home and winds up with yet another restraining order to add to his collection. Despite the brief length of the comic book icon's cameo in the series, Stan Lee was, inarguably, one of The Big Bang Theory's biggest gets in terms of star power—and he certainly made a lasting impression on both Sheldon and Penny.
Mark Hamill
Mark Hamill may not have been the first member of the Star Wars cast to make a guest appearance on The Big Bang Theory, but he, without question, had the most meaningful appearance in terms of what he contributed to the series. After Howard meets Hamill while returning a lost dog he found that turned out to be Hamill's, Mark Hamill offered Howard a favor as a show of gratitude for him returning his beloved pet to him.
The favor Howard requested, as we all know, turned out to be that Hamill would consider officiating Sheldon and Amy's wedding. Of course, all along, Wil Wheaton had been readying to do just that, which only furthered the dissension between Sheldon and Wheaton—especially given the Star Wars vs. Star Trek tension. But, Hamill turned out to be just the right man for the job, even getting emotionally invested multiple times during the ceremony.
James Earl Jones
It's often the most fun when a celebrity appears in a guest starring role as an exaggerated version of themselves. In season seven, Star Wars veteran voice actor James Earl Jones appeared in an episode that's so hysterically hard to believe it almost comes across as a fever dream. After Sheldon runs into James Earl Jones while dining out, the two embark on a bizarre, giddy adventure throughout the city.
Along the way, they visit a carnival, ride a Ferris wheel together, sing "The Lion Sleeps Tonight" at a karaoke night, take in a steam bath at a sauna, attempt to prank Carrie Fisher, and more. It's one of the series' most hilarious episodes ever, and none of it would have been possible without James Earl Jones' total commitment to the bit.
Bob Newhart
Few guest stars have contributed more meaningfully to the series overall than the comedy legend Bob Newhart. When Newhart first appeared on the series, he was the elderly former children's television show host Professor Proton—the man who inspired Sheldon to become a scientist—who found himself the unlikely object of Sheldon's interrogative devotion during their first meeting.
Over time, however, Newhart's role as Arthur deepened and became something so very much more meaningful. After Arthur's passing in the series, Newhart would continue to recur as a new version of the character, Force Ghost Arthur, who visits Sheldon in his dreams a la Obi-Wan Kenobi whenever Sheldon is in need of some moral support. No other actor could have made this character, and this recurring gag, so entertaining, and Newhart's halting, skeptical, quizzical delivery simply seals the deal each and every time.