Sitcoms have been a favorite pastime of television fans for a long time. They show no signs of going away. Especially today in the time of nail-biting dramas and hardcore epics, audiences sometimes need a break to relax and have a laugh.
While sitcoms do have their fair share of dramatic moments, they primarily need to excel in clever humor. Also, surprisingly, some of the funniest moments in sitcoms come from unexpected celebrity appearances.
With the popularity of sitcoms, it's no wonder creators and directors are given the chance to work with some famous faces (even if only for a single episode). In fact, some celebrities jump at the chance to appear on a sitcom, as many are fans of the shows themselves.
Like any other role, celebrities can play a variety of characters on sitcoms, from a one-time love interest to a blink-and-you'll-miss-it background appearance (and even a fictitious version of themselves).
So, it can sometimes be difficult for fans to spot their favorite stars, but, when they do, it can prove to be quite the hilarious surprise.
Some stars also appeared on sitcoms before they made it big in Hollywood, so they can sometimes be hard to spot.
However, there are eagle-eyed fans and trivia buffs who eventually discover the cameos and have a good laugh about it, whether this is because of how different the stars were then compared to today or because of how awkward the cameos were.
Here are the 20 A-Lister Cameos Fans Completely Missed In Iconic Sitcoms.
As another beloved series with a plethora of guest stars, Friends followed a group of six adult... well, friends living in Manhattan.
Among the most notable of the show's famous guests was actress Winona Ryder, who played Melissa Warburton in the 2001 episode "The One with Rachel's Big Kiss".
Melissa was a former sorority sister whom Rachel claims shared a passionate kiss with her in the past. While Melissa initially denies it, reenacting the kiss reveals that she not only remembered it, but that she has since harbored feelings for Rachel.
While Rachel does not feel the same way, she still gives her a kiss good-bye.
We guess this ended better than it would have if Ryder had been playing herself, since she was one of the names on Ross' list of women he could sleep with while dating Rachel in an earlier episode.
It's hard to believe, but The Rock played Rocky on That '70s Show - not the Italian Stallion of course, but his own father, WWE Hall of Famer Rocky Johnson.
In his first acting role, Johnson appeared on the 1999 episode "That Wrestling Show" to give Red Foreman an autograph... after discussing pile-driving midgets and predicting that his son will eventually become "the most electrifying man in sports entertainment."
Looking back on this episode, it's hard to decide what's more unusual: Johnson's meta prediction or the hair he sported.
Johnson isn't the only famous face to pop up in the series, though, as fellow wrestlers Ken Shamrock and Jeff and Matt Hardy showed up in the same episode.
Before becoming one of the world's most admired and highest grossing movie actresses, The Hunger Games star Jennifer Lawrence was starting out on television.
In one of her first roles, Lawrence appeared in a 2006 episode of Monk, titled "Mr. Monk and the Big Game", which focuses on the elimation of a high school basketball coach.
While Lawrence doesn't help with the case, she shows her school spirit as the mascot... until she pulls off her costume's head and says she needs to rest (unfortunately, her only other line was giving the score).
On the bright side, Lawrence's cougar costume was probably a cakewalk compared to the hours she would later spend in a makeup chair to transform into Mystique for the X-Men movies.
It's understandable why fans didn't initially catch this X-Men star on The Office (and not just because he plays Quicksilver).
Before his breakout role in American Horror Story, Evan Peters mainly portrayed supporting characters in TV, movies, and commercials.
In the season 7 premiere "Nepotism", Peters plays Luke Cooper, the nephew of Michael Scott, who hired him in order to reconcile with his half-sister.
However, when Luke proves to be a sorry excuse for an employee, Scott must take the situation into his own hands... by spanking Luke with his own hands.
No matter how many roles Peters takes on in his career, he will most likely never forget being whipped by Steve Carell - because that's something nobody can forget.
Another high-profile movie actor who got their start on television was Titanic star Leonardo DiCaprio.
In the same year young Leo had his debut film role in Critters 3, he also made a small appearance on the Roseanne episode "Home-Ec" as one of Darlene's Home Economics classmates.
Unlike Lawrence's role on Monk, DiCaprio didn't get to stand front and center or even speak in the episode, making his appearance harder to spot than some of the other entries on this list.
It's a good thing DiCaprio didn't stay silent and stick to bit parts, or fans of his work wouldn't have got to hear his numerous promotions of environmental awareness or see him get mauled by a bear in The Revenant.
Ted Mosby has had as many dates as this nine-year series has had guest stars, and it just so happens that Grammy-nominated artist Katy Perry got to be one of each.
In the sixth season episode "Oh Honey" in How I Met Your Mother, Perry plays the eponymous Honey (though her real name is never actually revealed thanks to Future Ted not remembering), the gullible cousin of another of Ted's love interests, Zoey Pierson.
Though Ted is set up with Honey, he leaves her in pursuit of Zoey, leaving Barney to try his luck with her (it doesn't work out either).
However, Honey didn't technically leave with nothing, as Perry's performance later won her the People's Choice Award for Favorite TV Guest Star.
With the only recurring celebrity role on this list, actress and model Brooke Shield certainly knows how to make the most of her time on a sitcom.
With six episodes in total from 2010 to 2018 on The Middle, Shield's role as Rita Glossner certainly stands out among the show's various characters.
Appearing as the Hecks' bad-mannered neighbor, Shields doesn't look or act like her usual self, sporting a mullet and off-season tan.
The fact that she is a single parent to four boys also doesn't put her in the best of moods, especially since she had to kick their father out years ago.
Yikes. It sounds like the Hecks needed a shield to protect themselves from Brooke.
After practicing her soon-to-be legendary comedic chops on Live at Gotham and Last Comic Standing in the mid-2000s, it's no wonder that comedian and actress Amy Schumer eventually landed a role on NBC's satirical hit series 30 Rock.
Playing a stylist in the episode "'Mamma Mia", Schumer was tasked with preparing Liz for a cover shoot.
Fans will know that this wasn't the last time the two stars would be seen together, as they recently hosted an episode of Saturday Night Live and shared an infamous kiss at the Peabody Awards.
While she's only onscreen for mere moments, Schumer fans will still be happy knowing that she got in one line: "Ugh, I'm gonna get some tape."
Actor Dax Shepard has recently gained attention for his starring roles in Parenthood and CHiPS (which he also directed), but fans may have a hard time remembering his 2015 guest appearance in the long-running dark comedy It's Always Sunny in Philadelphia.
In the episode "Ass Kickers United: Mac and Charlie Join a Cult", Shepard appears as Jojo, a member of the cult that Charlie and Mac get involved with (which was made up by Dennis to protect his Thin Mints).
While Charlie and Mac make it out okay, things don't work out so great for Jojo, who volunteers to set himself on fire in order to please the cult's "Supreme Overlord Master."
Or, perhaps Shepard was just preparing for another Punk'd revival?
When it first started, many people probably had their doubts about a show centering around four geniuses and a blonde waitress.
However, through The Big Bang Theory's clever fandom references and deadpan humor courtesy of Sheldon Cooper, it has become popular enough to warrant twelve seasons.
With its popularity has come a vast assortment of fandom and science-related appearances, from Marvel god Stan Lee to the late, great theoretical physicist Stephen Hawking.
This is why it was no surprise to anyone that SpaceX founder Elon Musk appeared as himself. It was a surprise, however (especially to Howard), to see him working in a soup kitchen on Thanksgiving.
In "The Platonic Permutation", Howard's dislike for volunteering vanishes when he gets a chance to talk to Musk about his time in space and share a piece of pumpkin pie.
The Wonder Years was one of the best shows to watch in the '80s, telling the coming-of-age story of Fred Savage's Kevin Arnold.
However, Savage wasn't the only notable young actor on the show, with Clueless star Alicia Silverstone playing her first credited role in the episode "Road Test".
Silverstone appears as Jessica Thomas, one of Savage's many love interests who wants him to pick her up in a car.
However, since the episode revolves around Kevin's inability to parallel park (don't worry, he eventually gets his license), she doesn't stick around for too long.
The guys on this show certainly knew how to find girlfriends who would grow up to be famous, as Juliette Lewis and Carla Gugino also appeared as two of Wayne's girlfriends.
Jon Hamm's Golden Globe-winning performance of Don Draper in Mad Men saw him encountering some tough adversaries in the advertising world. However, Draper had never met a person like Amy Poehler's Leslie Knope.
The season six finale of Parks and Recreation "Moving Up" fast forwards three years into the future to show Leslie firing Hamm's incompetent National Parks Service employee, Ed.
Fortunately, Ed takes it with a smile before thanking her for "literally hundreds of opportunities."
Showrunner Mike Schur said he would've loved to have Hamm in several episodes with "a shot of him doing something insanely incompetent."
While Hamm's spot didn't last long, he would return the following season, along with other former Parks guests Rob Lowe and Rashida Jones.
It wouldn't be a list of top sitcom guest stars without including Family Guy, the long-running animated series that is famous for its cut-away gags that sometimes feature special guest appearances.
However, while several stars play fictional versions of themselves, Grammy-nominated star Ariana Grande (who previously acted on Nickelodeon's Victorious and its spinoff Sam & Cat) only played a brief role in the episode "Mom's the Word".
When Stewie tells Brian that the Italian family next door has been arguing, audiences can hear Grande, who is credited as "Italian Daughter," asking her father for lunch money.
Her father then sarcastically says he'll get some out of his "room of golden jewels."
It sounds like Grande would have one less problem without that guy.
While this Oscar-winning actor hasn't acted since 2010's How Do You Know (which may change soon), Jack Nicholson has already left quite the legacy for himself in film.
In his early years, Nicholson had a few spots on certain TV series, one being the iconic Andy Griffith Show.
Being the only celebrity on this list to play multiple characters, Nicholson appeared on the show in both 1966 and 1967.
His first role was a brief appearance as Mr. Garland in "Opie Finds a Baby", where he played the father of the couple whose child Opie finds and takes care of.
He later portrayed an expanded role as Marvin Jenkins in "Aunt Bee, the Juror", where Jenkins is accused of thieving and the jury wants to condemn him - all except Aunt Bee.
Just be sure not to give him the bat, Aunt Bee.
As a man known for his love of violence and vulgar language (on film, at least), acclaimed director (and occasional actor) Quentin Tarantino would be an ideal guest star for a dramatic series like Game of Thrones, but it's hard to imagine him appearing on a show like The Golden Girls.
Before directing his debut movie Reservoir Dogs, Tarantino tried a variety of jobs, including an adult theater usher, a video store clerk, and an aerospace industry recruiter.
However, fans may not know that he made a brief appearance on the hit NBC show.
In the episode "Sophia's Wedding: Part 1", Tarantino appears as one of several Elvis impersonators.
While this may make him hard to find for some (hint: check the back row), he certainly put effort into the role, reportedly dressing not as flashy as the others to capture "the Sun Records Elvis."
Actor and Seinfeld co-creator Larry David has had several celebrities play themselves on his long-running show Curb Your Enthusiasm, including Ted Danson, Michael J. Fox, and the entire main cast of Seinfeld.
However, upon going to a Los Angeles Lakers game, not only did David run into legendary basketball star Shaquille O'Neal, but he also accidentally trips him, putting the Lakers' season in risk.
Luckily, this works out in David's favor, as his friends stop asking him for favors.
O'Neal also turns out to be a big Seinfeld fan, forgiving David after he brings him a complete collection of the series' VHS tapes.
O'Neal has had his own movie career and has appeared in commercials and video games (as well as an upcoming sequel), but having a sitcom episode titled "Shaq" certainly takes the cake.
This is yet another first acting credit for another famous name. Actor Armie Hammer (who recently gained acclaim for his role the Best Picture-nominated movie Call Me By Your Name) first showed his face to a worldwide audience on the popular on-again-off-again show Arrested Development.
One can definitely believe that this is Hammer's first role upon learning his credited character name: student #2.
In the episode "The Immaculate Election", George Michael's class president campaign is thrown into chaos when his uncle Gob accidentally releases George's "Star Wars kid" video for others to see.
While George is busy being embarrassed, Hammer walks by and points at him, saying "Hey, Star Dork!"
When one wants to mock a fellow student, it's always best to bring a one-man Armie.
Oscar-nominated actress Michelle Williams has managed to stay in the public eye for 20 years, starring in TV drama Dawson's Creek from 1998 to 2003 and set to star in Sony's upcoming superhero movie Venom.
Just two years after her acting debut in 1993, she made a guest appearance on the popular ABC sitcom Home Improvement.
Don't get the wrong idea, though, since she appears in the episode "Wilson's Girlfriend". She thankfully plays Brad's girlfriend Jessica Lutz.
However, like many young men and women, Brad gets an embarrassing pimple and uses his mom's makeup to cover it up.
Williams unfortunately never returned to the show, probably because of the long line of young men waiting to date her.
Another must-have show to have on any list of sitcoms is Seinfeld, the acclaimed "show about nothing." Many fans consider it the greatest TV series of all time.
While actor and singer Drake Bell became well-known for his starring role on Nickelodeon's Drake & Josh (and later becoming the voice of everyone's favorite web-head on Disney XD's Ultimate Spider-Man), he probably will never forget earning a guest spot on one of the biggest shows of all time.
In the final season episode "The Frogger", Bell plays a young boy named Kenny whom George and Jerry find in a pizzeria. There, Bell is seen playing the classic arcade game Frogger.
He's not on screen for long and is mainly focused on playing his game... until George makes him lose while trying to give him some tips.
Come on, George. Leave the gaming to the professionals.
This successful Cheers spinoff had its fair share of celebrity appearances, even though they didn't physically appear.
Yes, various celebrities, including Christopher Reeves and Helen Mirren, had voice roles as patients calling in on Frasier's radio show.
A notable celebrity caller was the "King of Horror" himself, author Stephen King. However, instead of harnessing his power of fright, King uses his talent for snappy remarks.
In "Mary Christmas", Dr. Crane tells callers that he has only one minute left before the news. He tries to squeeze in caller Tom (voiced by celebrity chef Wolfgang Puck, who went on to appear as himself in the next season), but he insists that he'll wait.
Up next is King's Brian, who after hearing Crane's signature "I'm listening" replies "For what? 30 seconds? I'll wait, too."
Can you think of any other A-listers who had cameos in iconic sitcoms? Sound off in the comments!