Lasting 12 seasons and reaching millions of viewers across the globe,The Big Bang Theoryis one of themost successful sitcoms of all time. It focuses on a group of socially awkward scientists and their interactions with each other and the world around them. Celebrating “geek” culture and science humor, the show has amassed a huge following and boasts some of the biggest celebrity guest appearances of all time.
The Big Bang Theory
With literally dozens of famous guest appearances and cameos under its belt, some are truly unforgettable, like James Earl Jones’ “ring and run” prank on fellowStar Warsactor Carrie Fisher’s home or Wil Wheaton’s recurring role as a darker, egomaniacal, fictionalized version of himself. Other memorable appearancesinclude Mark Hamill, Stephen Hawking, Stan Lee, and William Shatner.
Here, we’ve listed 10 other great celebrity appearances inThe Big Bang Theorythat you may well have forgotten about.
10Eliza Dushku
Season 4, Episode 7 - “The Apology Insufficiency”
Eliza Dushku rose to prominence in the ‘90s and ‘00s, starring in a number of major movies, includingTrue Lies,Wrong Turn, andJay and Silent Bob Strike Back. She was certainly no stranger to television either, having also appeared as Faith in the supernatural drama seriesBuffy the Vampire Slayer(1998–2003) and its spin-off seriesAngel(2000–2003). In 2010, she appeared inThe Big Bang Theory’s Season 7, Episode 4 as Angela Page, an FBI Special Agent brought in to check Howard’s background before granting him security access to work on a new project.
As Expected, Things Don’t Go to Plan
When interviewing Howard’s friends to assess his character, they are intimidated by Angela’s looks and position of power, and each, in their own way, only makes matters worse for Howard. Raj can only find the confidence to talk to her when drunk, Sheldon is far more interested in his own experiences with the FBI than in Howard, and Wolowitz seizes the opportunity to attempt to seduce the agent.
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9Sarah Michelle Gellar
Season 12, Episode 24 - “The Stockholm Syndrome”
Eliza Dushku is not the onlyBuffy the Vampire Slayeralum to have guest-starred; Buffy herself, Sarah Michelle Gellar, also once appeared. Playing herself, she is seen sharing a flight with the main cast of characters and later attending the same Nobel Prize ceremony.
Unsurprisingly, Buffy and Sarah Michelle Gellar Are Much Loved by the Characters
Leonard, Howard, Sheldon, and Raj share a strong appreciation for sci-fi, fantasy, ‘nerd’ culture, and cult television shows, so it’s no surprise that they are hugefans ofBuffy the Vampire Slayer. Upon discovering Gellar’s presence among them, their deep admiration is perfectly captured by their stunned reactions, nervous energy, and awkward attempts to impress her.
8Elon Musk
Season 9, Episode 9 - “The Platonic Permutation”
Back when Elon Musk was known more as a tech innovator than the controversial, headline-grabbing, and politically outspoken persona he is today, he appeared as himself in the ninth episode of the ninth season ofThe Big Bang Theory. His appearance continued the trend of including guest stars from the world of science and technology, following the likes of Stephen Hawking and Apple co-founder Steve Wozniak before him.
Elon Musk Was Working in a Soup Kitchen at a Homeless Shelter
Appearing in 2015’s Thanksgiving episode, Howard encounters Musk while working in the soup kitchen of a homeless shelter. While working together to help the less fortunate, the two bond over their shared interest in space travel. Far from the most memorable guest cameo by a long shot, one couldn’t help but wonder what the reaction would be like today, following Musk’s newfound notoriety.
7Howie Mandel
Season 6, Episode 4 - “The Re-entry Minimization”
Television personality and actor Howie Mandel appeared in the episodeThe Re-Entry Minimization, during which he shares a flight with Howard, who is returning home after achieving a lifelong dream of traveling to space.
There’s a Hilarious Mix-Up Between ‘Howard’ and ‘Howie’
As Howard arrives at the airport alongside Mandel, he hears a crowd chanting “Howie” as they rush to take photos. Believing they are celebrating his return from space, he steps into the limelight and begins to deliver a speech, only to be interrupted by Mandel, who explains they are there for him. This hilarious mix-up is a prime example of the show’s sharp humor, where awkward social blunders and popular culture collide.
6Charlie Sheen
Season 2, Episode 4 - “The Griffin Equivalency”
Charlie Sheen was, at the time,starring inTwo and a Half Men, another sitcom from producer Chuck Lorre. In a very brief cameo, he appears as himself inThe Big Bang Theoryat a party where Raj is celebrating his discovery of a planetary object finally being recognized, enthusiastically sharing with everybody that he was going to be inPeoplemagazine. Charlie Sheen— in a self-mocking response to this—then delivered the iconic line,“Yeah, call me when you’re on the cover.”
Charlie Sheen Is Not a Fan of the Show
In a 2013 interview while promoting his new showAnger Management, Sheen’s cameo came up, and he made it clear he was not a fan. He was quoted as saying it was"stupid,““lame,“and"about lame people,“also referring to it as"a piece of s**t.“He then went on to state that the show wouldn’t have even been possible withoutTwo and a Half Menpaving the way for it.
5Adam West
Season 9, Episode 17 - “The Celebration Experimentation”
Following a traumatic childhood incident in which he was falsely led to believe that Batman would be attending his birthday party, Sheldon admits he has never been able to enjoy a birthday party since. In a sweet and thoughtful gesture, his friends manage to hire iconic actor Adam West, best known forhis portrayal of Batmanin the ’60s, to attend his party.
Adam West Isn’t the Only Guest Cameo
Things get even better for Sheldon when he receives a video call from his hero, Professor Stephen Hawking, who joins them in singing"Happy Birthday.“Hawking made numerous appearances on the show throughout its run, appearing in a total of seven episodes.
4Nathan Fillion
Season 8, Episode 15 - “The Comic Book Store Regeneration”
Nathan Fillion is best known for playing the leading role of Captain Malcolm “Mal” Reynolds inFireflyand its film continuation,Serenity. He appears inThe Big Bang Theoryas himself, eating at a deli and trying to mind his business. This proves to be harder than anticipated when he is spotted by Raj and Leonard.
An Awkward Encounter
After being spotted, Nathan Fillion initially denies he is an actor, but after being questioned, he admits they are right. By this point, though, Raj has grown suspicious and pushes Fillion to prove his identity by answering questions based on hisFireflycharacter. The entire encounter is both awkwardly funny and endearingly nerdy, demonstratingThe Big Bang Theory’s talent for utilizing its celebrity guests.
3Kevin Smith
Season 12, Episode 16 - “The D&D Vortex” and Season 8, Episode 20 - “The Fortification Implementation”
Kevin Smith is ageek cultureicon. The comic book enthusiast and director of cult classics likeClerksandMallratswas the perfect match forThe Big Bang Theory. At first, it’s just his instantly recognizable voice we hear on the show in Season 8, where he appears as himself on Wil Wheaton’s podcast and offers Penny an audition for a newClerksmovie.
Kevin Smith Returned in Season 12
In what is quite possibly the most celebrity-filled episode of the show’s history, Kevin Smith returned to join Penny, Amy, and Bernadette, along with William Shatner, Wil Wheaton, Joe Manganiello, and Kareem Abdul-Jabbar, for a game ofDungeons & Dragons. Probably most memorable for Shatner finally appearing on the show after years of speculation, it’s nice to witness Smith injecting plenty of humor himself, hilariously asking Shatner to put a dollar in theStar Trekjar after he says he’s going to go allWrath of Khanon them.
2Christopher Lloyd
Season 10, Episode 10 - “The Property Division Collision”
The legendary character actor, known for his roles inTaxi,One Flew Over the Cuckoo’s Nest,Who Framed Roger Rabbit, and,of course,Back to the Future, appeared inThe Big Bang Theoryback in 2016. He plays an elderly man named Theodore, who shares Sheldon’s room after Sheldon sublets it to him to spite Leonard.
Lloyd Brings His Trademark Eccentricity
Theodore is strangely endearing and amusingly oblivious to the drama that unfolds around him. With the perfect blend of laid-back, deadpan delivery and Lloyd’s trademark eccentricity, he adds an almost surreal element to the dynamics as he nonchalantly goes about his business, offering quirky advice that proves to be far more useful than expected.
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1Billy Bob Thornton
Season 8, Episode 7 - “The Misinterpretation Agitation”
Hollywood icon Billy Bob Thornton played a successful but socially awkward doctor who mistakes Penny’s flirtatious sales technique for a genuine connection. After discovering Penny is with Leonard, he lures him and his friends down to his basement, filled with sci-fi memorabilia, locks them in, and goes to pursue Penny once more. Things take an even more bizarre turn as he falls for Amy en route and later for Bernadette.
Billy Bob Thornton’s Appearance Was Miraculously Kept Under Wraps
In an age where spoilers freely leak long before episodes debut, the Oscar winner’s appearance was somehow successfully kept a secret, making the surprise all the more rewarding. Audiences and critics responded positively to his layered portrayal of a deeply entertaining but confused individual.
