The Big Bang Theory: 10 Funniest Guest Stars

One of the major reasons for The Big Bang Theory‘s wild success was its incredible ensemble of actors. The seven main characters developed a unique and compelling bond, elevating even the show from an otherwise average sitcom into a true icon of modern television.

However, The Big Bang Theory also had multiple guest stars who left their mark on the series. Some of these actors played recurring roles throughout the twelve seasons, while others only appeared in one episode. Still, they were all hilarious, with some even becoming fan favorites thanks to how funny they were.

Professor Crawley

“The Jiminy Conjecture” is far from being one of The Big Bang Theory‘s classic episodes. Still, it’s a solid entry in the show’s third season, mainly because of Lewis Black’s memorable turn as Professor Crawley, Caltech’s resident entomologist.

Black expertly plays Crawley’s bitterness, turning pure anger into uproarious comedy. He only has one scene, but that’s all he needs to make an impression. Few comedians are as gifted or as unique as Black, and his turn as Professor Crawley is yet another confirmation of his vast talent.

Wyatt

Most of Penny’s family remains a secret for much of the show’s duration, except for his father. Played by Keith Carradine, Wyatt first appears in season three, after Penny and Leonard have already broken up. However, she’s afraid to tell him, and the two pretend they’re still together, much to Leonard’s delight.

Wyatt returns several times throughout the show’s future seasons, acting as the voice of reason in Penny’s life. He has a laid-back attitude that makes his humor all the more entertaining. Whether he’s telling Penny her pig died or trying to keep his family from killing each other, Wyatt is always a hoot.

Wil Wheaton

Fans of the show know that Sheldon has numerous people on his enemies list, among them Wil Wheaton. The brilliant physicist holds a grudge against the Star Trek actor because he failed to show up at a convention Sheldon attended as a child.

Wil and Sheldon share a hilariously antagonistic relationship during seasons 3, 4, and 5, although they eventually become friends. Wil then becomes less funny, but he remains a pleasant presence in the show; besides, fans will always have those first episodes where Wil’s nastiness is extremely entertaining and humorous.

Stephen Hawking

Not many people would’ve guessed that Stephen Hawking would be such a great sport. The world-famous scientist appeared numerous times in The Big Bang Theory, playing a fictionalized version of himself who becomes friendly with Sheldon.

Hawking’s many participations in the show showcase his willingness to not take himself seriously. He plays Words with Friends with Sheldon during one memorable episode, mocking him when he loses and comparing him to a black hole because “they both suck.” Seeing such a prominent and respected figure getting down and dirty on a sitcom would be enough, but Hawking is genuinely funny, making things a thousand times better.

Dr. Oliver Lorvis

Not many people remember that Billy Bob Thornton is an Oscar nominee; in fact, the actor actually claimed the trophy in the Original Screenplay category. Nowadays, Thornton is best known for his television roles in shows like Fargo and Goliath, but Big Bang fans recognize him as Oliver Lorvis, a socially-awkward client of Penny’s with an unrequited crush on her.

Although Lorvis only appears in one episode, season eight’s “The Misinterpretation Agitation,” Thornton’s performance is so hilariously awkward that the character became an immediate standout. The actor plays Lorvis’ quirks with clumsiness, making the doctor funny without ever being creepy.

Mary Cooper

Sheldon’s mother Mary is a series staple from the first season. Played by one of television’s most acclaimed actresses, the mighty Laurie Metcalf, Mary is a devout Christian who’s highly intolerant to sin. Still, Mary loves and supports her son, showing remarkable patience towards him despite his numerous idiosyncrasies.

Not everything is perfect, and Mary has multiple flaws, including her overt racism. The show often tries to find humor in her stereotypical views, but what was funny in 2007 is less so in 2022. Still, Mary is a vital part of Big Bang, a likable and funny character, mainly thanks to Metcalf’s considerable talents.

Zack Johnson

Penny has her fair share of relationships during the show’s early seasons. However, one of her most memorable affairs is with Zack Johnson, a sweet and friendly but young man who’s as handsome as he is vacuous.

Indeed, Zack is overly simple, and much of the humor comes at his expense. Still, he’s an endearing and beloved character that fans enjoy watching. In fact, some viewers consider Zack The Big Bang Theory‘s most underrated character, and with good reason.

James Earl Jones

Star Wars is one of the guys’ favorite franchises, and the show had several of its actors as guests. However, the funniest and most memorable star to visit Big Bang was James Earl Jones playing a highly fictionalized version of himself.

When Sheldon fails to secure Comic-Con tickets, he tries to create his own convention with Jones as a panelist. Unlike other famous people who run at the sight of Sheldon, Jones embraces the kooky scientist, taking him to the fair, a karaoke bar, and an ice-cream parlor. Jones behaves like a child throughout the episode, creating a portrayal that’s as wholesome as it’s hilarious.

Beverly Hofstadter

The Big Bang Theory had several television legends playing guest roles, including Christine Baranski. The actress, already renowned for her scene-stealing turn in the 1990s comedy Cybill, played Leonard’s cold and distant mother, Beverly Hofstadter.

Most of Beverly’s comedy came from her robotic personality and her blatant disregard for Leonard’s needs and wants. Elevated by Baranski’s deliciously glacial delivery, Beverly’s words cut deep but were hilarious nonetheless. The show ends with Leonard and her reconciling, but it’s clear they will never be close.

Arthur Jeffries

In season 6, television icon Bob Newhart made his first appearance as Arthur Jeffries, AKA Professor Proton, quickly becoming one of the show’s highlights. Professor Proton is Sheldon and Leonard’s childhood hero, the star of a children’s science show and the reason the two got interested in physics in the first place.

Professor Proton would return several times, appearing in seasons 6, 7, 9, 11, and 12. Thanks to Newhart’s trademark deadpan delivery and his commitment to elevating the material, Professor Proton soon became one of The Big Bang Theory‘s best secondary characters. The role also won Newhart a long-overdue Emmy Award, and that’s reason enough to celebrate.

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David Caballero
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David is a twenty-eight-year-old Mexican writer and reader. Having studied Marketing in school, he spent three years working a nine-to-five desk job before deciding to pursue a writing career. He now works as a Senior Writer in ScreenRant and does some more freelancing job, talking about the entertainment business he so loves. Currently, he’s also writing his second novel while actively working to get his first one published.

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