It’s Always Sunny In Philadelphia: Best Guest Stars, Ranked

It’s Always Sunny in Philadelphia has been on television for almost two decades, and while the lead characters running Paddy’s Pub are the series’ biggest appeal, several It’s Always Sunny guest stars have stolen the show. Surprisingly, It’s Always Sunny in Philadelphia’s formula hasn’t gotten old, as the show has rarely strayed from what made it successful, which is the so-called best friends and co-owners of Paddy’s Pub constantly stabbing each other in the back for personal gain.

However, while It’sAlways Sunny in Philadelphia has an incredible main cast, including Glenn Howerton (Dennis), Charlie Day (Charlie), Rob McElhenney (Mac), and Danny DeVito (Frank), It’s Always Sunny guest stars have become some of the most lovable characters. The Gang has often played second fiddle to some big-name actors. Some guest stars have reprized their roles multiple times because their characters are that good, but other guest appearances left fans feeling they could’ve done without them.

22 Retta As Hardware Store Clerk

“The Gang Gets Extreme: Home Makeover Edition”

Retta is best known for her role as Donna Meagle in Parks and Recreation — the girl knows how to treat herself, as evidenced by her famous meme. But her appearance in It’s Always Sunny was so small that it’s easy to miss. In season 4, episode 12, “The Gang Gets Extreme: Home Makeover Edition,” Charlie and Dennis go shopping after kidnapping the Juarez family, and they are now forcefully renovating their house. This means they need supplies and head to the hardware store.

Retta plays the clerk at the hardware store where the gang is picking up the supplies. Like many other guest stars, Retta plays it straight and has to listen to Charlie’s ludicrous ideas. The guest star is fun for fans of Parks and Recreation, but she doesn’t have much material to work with. She doesn’t get the chance to say much, but her facial expressions are brilliant in response to Charlie’s comments. Retta also stars in the TV show Good Girls and has a role in the movie Good Boys.

21 Brian Huskey As Gary

“2020: A Year in Review”

Brian Huskey features in season 15, episode 1 of It’s Always Sunny in Philadelphia, “2020: A Year in Review.” The episode has one of the most unique concepts in the series, as it takes advantage of all the catastrophic events in 2020 and suggests that the gang was heavily involved in all of them. This happens when Gary (Brian Huskey) audits the gang after the Paddy’s Pub owners fail to repay several PPP loans.

Huskey’s reactions to the gang’s stories are priceless. He can’t believe they were responsible for so many of the bad things that happened in 2020, although a montage shows they were completely to blame. Huskey appeared in Ant-Man as one of Cassie’s school teachers, but his voice is more recognizable than anything else, as he’s voiced various Bob’s Burgers characters. He also appeared in Children’s Hospital and People of Earth.

20 David Huddleston As Eugene Hamilton

“A Very Sunny Christmas”

One of the more surprising It’s Always Sunnyguest stars occurred when the show creators brought in the other Lebowski from TheBig Lebowski. Huddleston is best known for his role in the cult classic Coen brothers film as the billionaire that the Dude gets mistaken for, and his appearance in It’s Always Sunny in Philadelphia might have become his second-best-known role.

The comedy legend plays Frank’s old business partner in the special “A Very Sunny Christmas,” which sees him heavily involved in one of the gang’s ridiculous schemes as he tries to convince Frank he’s a ghost before threatening to kill Frank. Huddleston also played one of the Johnston brothers in Blazing Saddles. Sadly, It’s Always Sunny was one of Huddleston’s final roles. The episode was in 2009, and he only appeared in a Gilmore Girls episode before he died in 2016.

19 Pablo Schreiber As Ricky Falcone

“A Very Sunny Christmas”

Pablo Schreiber is best known for playing George Mendez in Orange Is The New Black, who was overly creepy and even had the nickname “Pornstache.” However, he was a lot less creepy during his appearance on It’s Always Sunny, in which he played Ricky Falcone, a man whose toy robot had been stolen by Mac on Christmas many years ago. The appearance is in the It’s Always Sunny holiday episode titled “A Very Sunny Christmas.”

Mac feels guilty decades later and decides to return it, but he typically makes Eddie’s life worse and even bullies him about his depressed lifestyle. They go on to try to buy toys for Ricky’s children, but this only makes things even worse in the end. Being one of the earlier episodes, Schreiber is one of the most underused It’s Always Sunny guest stars. On top of appearing in Orange is the New Black, Schreiber also appeared in Weeds, The Wire, Den of Thieves, and Halo.

18 Rob Thomas As Himself

“Dennis Reynolds: An Erotic Life”

Rob Thomas’ appearance is one of the most random It’s Always Sunny guest stars since he’s a singer and not an actor. However, the celebrity’s appearance during season 4, episode 9, “Dennis Reynolds: An Erotic Life,” is one to remember — and it’s one of the wildest casting decisions ever. However, considering the episode featured Dennis experiencing hallucinations and paranoia, it surprisingly makes sense.

The musician has since revealed how he got the gig, as Thomas invited the Always Sunny cast to a concert, which led to them offering him a part in the show. “We were just fans – and Matchbox was playing the Staples Center,” Thomas said (via Audacy). “We just called their management and were like, ‘Hey, we’re big fans. You should come to the show.’ And they came early [and hung] out the whole day. We got drunk after the show together, and by the end, they were just like, ’You’re gonna be on the show.’”

17 Sinbad As Himself

“Dennis Reynolds: An Erotic Life”

Rob Thomas is one of the strangest It’s Always Sunny guest stars, but what’s even stranger is who guested alongside him. Along with Thomas, Sinbad, a comedian and actor who is best known for his role as Myron Larabee in the cult classic Arnold Schwarzenegger Christmas movie Jingle All the Way, featured in the same scenes.

In the episode, Thomas and Sinbad play two patients in a mental institution who harass Dennis. Sinbad hilariously kept reminding everyone in the episode that Rob Thomas was the lead singer from Matchbox 20. “That’s Rob Thomas. Matchbox Twenty. Sing a song,” Sinbad yelled. When Rob started to sing, Sinbad yelled, “Shut up!” While Rob Thomas was great in his role (especially with his facial expressions), Sinbad stole the show with his performance in this episode.

16 Geoffrey Owens As “Middle Aged Guy” (Possibly Himself)

“Frank’s Pretty Woman,” “The Gang Gets Invincible,” “The Gang Makes Lethal Weapon 7”

Geoffrey Owens is one of the most interesting It’s Always Sunny guest stars. He has appeared three times and plays an actor hired by the gang each time. The actor has played “Fake Tiger Woods,” “Fake Donovan McNabb,” and “Fake Don Cheadle” in several of the gang’s schemes. Each time, he doesn’t look happy to be there and is simply picking up a paycheck, which makes it that much funnier.

Though it isn’t clear, Owens could very well be playing a fictionalized version of himself, as Mac and Dennis reference the fact that he starred in The Cosby Show. In real life, Owens played Elvin Tibideaux (the husband of Sondra Huxtable) in the sitcom. Fans might also remember Owens for his roles in The Good Fight, Power, and Ghosts. He also appeared in movies such as Fatale, Hide and Seek, and Ezra.

15 Dax Shepard As Jojo

“Ass Kickers United: Mac and Charlie Join a Cult”

Dax Shepard has played some pretty weird characters in his career, such as Frito Pendejo in Idiocracy and Vince in Employee of the Month, so it only makes sense that he’d have the weirdest role of his career when he became an It’s Always Sunny guest star. It was a cameo in season 10, episode 10, “Ass Kickers United: Mac and Charlie Join a Cult,” where he becomes one of the followers in the cult that Charlie and Mac joined.

Shepherd is great at playing dim characters, and his role as Jojo, a cult follower who religiously puts stickers on his face, is the epitome of exactly that. Dennis started the cult to make Mac stop eating all his cookies, but the ending for Jojo was hilarious. When a fire breaks out at Dennis and Mac’s apartment, Jojo throws himself on it and is also seen riding a turtle through space. It ended up being a great role that many fans have already forgotten about.

14 Dennis Haskins As Coach Murray

“Charlie Got Molested”

Dennis Haskins as the lovable principal Mr. Belding in Saved By the Bell, and he was also one of the earliest It’s Always Sunny guest stars. During his stint in season 1, episode 7, “Charlie Got Molested,” Haskins plays the gang’s old teacher, who was accused of molesting children. At this point, Mac wants to prove the former teacher is guilty and attempts to seduce the teacher by dressing in his old gym shorts.

They, of course, learn in the end that the teacher was innocent and was actually falsely accused of wrong-doing (which Charlie was saying all along anyway). Haskins’s former co-star, Patrick Thomas O’Brien, coincidentally, also played a teacher in It’s Always Sunny in Philadelphia season 2, episode 8, “The Gang Runs For Office.” Haskins also had cameos in other sitcoms, including New Girl and How I Met Your Mother.

13 Christopher Lloyd As Santa Claus John

“A Very Sunny Christmas”

Christopher Lloyd, who is an ’80s icon and has starred in Back to the Future, Clue, Who Framed Roger Rabbit?, and joined Mandalorian season 3, has one of the best cameos of all the It’s Always Sunny guest stars, as even fans of Back to the Future didn’t recognize him. It’s ironic that the most recognizable actor with the most prolific career of the best Always Sunny guest stars is so hidden that he’s easy to miss.

The actor was hidden behind a white Santa beard in the “Always Sunny Christmas Special.” In a flashback scene, he visits Charlie’s mother on Christmas, and this memory causes Charlie to react violently when he realizes who Santa really is. This causes Charlie to take all his frustrations out on a poor, unsuspecting Mall Santa Claus. This was a huge cameo guest role on It’s Always Sunny, and it could have been given to a better actor.

12 Josh Groban As Himself

“Mac’s Mon Burns Down Her House”

Josh Groban isn’t just a great musician; in season 6, episode 6, “Mac’s Mom Burns Down Her House,” he proved that he’s also a great comedy actor. Groban was cast as Dee’s short-lived boyfriend, though she eventually breaks up with him during a daydream in favor of Brad Pitt. Unfortunately, while It’s Always Sunny has often leaned into its musical elements, they didn’t really utilize his singing talents or any of his songs in this episode.

While the sequence with Groban was funny, he was underutilized, and his musical talents could have been used for a Nightman sequel, a follow-up episode that has been in demand for so long. Groban’s other TV credits include NBC’s The Office, where he played Andy Bernard’s (Ed Helms) brother. He also appeared on CBS’ CSI: NY, where he played himself and performed a song on that show, something that was lacking in his It’s Always Sunny guest role.

11 Keegan-Michael Key As Grant Anderson

“The Gang Goes on Family Fight”

Leave it to the gang to somehow end up on a Family Feud-inspired game show, which was aptly titled Family Fight. As hilarious as the concept is on its own in season 10, episode 8, “The Gang Goes on Family Fight,” it was made all the better when Keegan-Michael Key was invited to play the part of the host. He interacts with the gang as they try to (and fail at) answer the trivia questions.

His part-parody of Steve Harvey, along with mocking the Paddy’s Pub gang, makes Key easily one of the best It’s Always Sunny guest stars. This was also one of Rob McElhenney’s favorite guest stars. “There’s an episode where we go onto a family feud type show called Family Fight, and it was something that I wanted to do,” McElhenney said (via Collider). “Keegan Michael Key plays the host of the show. He’s just so brilliant. That’s an episode I’m proud of. I think it’s really funny.”

10 Alexandra Daddario As Ruby Taft

“Charlie and Dee Find Love”

Alexandra Daddario’s role in It’s Always Sunny in Philadelphia is hardly a guest star role, as the popular actor wasn’t too famous when she appeared in season 4, episode 8, “Charlie and Dee Find Love.” However, this early role shows how much of a screen presence she has. Before making waves in 2017’s Baywatch remake and playing Rachel Patton in The White Lotus, Daddario briefly played Charlie’s love interest.

To this day, Dadarrio’s character, Ruby Taft, is the only woman who’s made Charlie forget about his obsession with the waitress. Daddario has gone on to a hugely successful career since her appearance on It’s Always Sunny in Philadelphia. She has appeared in San Andreas as Blake Gaines, American Horror Story: Hotel as Naacha Rambova, and took on the lead role in the Anne Rice universe’s Mayfair Witches as D. Rowan Fielding.

9 Stephen Collins As Bruce Mathis

“Dennis and Dee Get a New Dad,” “Dennis and Dee’s Mom Is Dead”

Stephen Collins made a name for himself as the Reverend and father-of-seven in 7th Heaven, which makes it ironic that he played Dee and Dennis’ biological father in It’s Always Sunny in Philadelphia, given how raunchy it is. Collins was featured in the season two finale where it was revealed he was the biological father of the twins, and he double-bluffed Dee and Frank when they were trying to scam him.

Though Dee and Dennis were initially swayed by his morally altruistic attitude, they soon realized that sort of life just isn’t for them. This is one of the very best It’s Always Sunny guest appearances. On top of these two appearances, Collins is also known for his role as William Decker in Star Trek: The Motion Picture in 1979, Dayton King in the TV show No Ordinary Family, and as Gene Porter in the NBC series Revolution.

8 Jason Sudeikis As Schmitty

“The Gang Gets A New Member”

Jason Sudeikis played the role of Schmitty in season 6, episode 8, “The Gang Gets A New Member.” His appearance was actually highly foreshadowed in the show. He was first mentioned in season 3, episode 3, “Dennis and Dee’s Mom Is Dead,” but he was never shown on screen until the sixth season. Sudeikis reprises his character again in season 7, episode 13, “The High School Reunion, Part 2.”

Sudeikis’s role as the annoyingly likable Schmitty is one of the most notable It’s Always Sunny guest appearances. Thanks to the success of Ted Lasso, Sudeikis has become one of the most popular TV actors, playing the title role in that Apple TV+ comedy series. He also co-starred with It’s Always Sunny in Philadelphia star Charlie Day in Horrible Bosses, and he voices Red in the Angry Birds movie franchise and Hit-Monkey in the Hulu Marvel animated series.

7 Oscar Nunez As The Sudz Manager

“The Gang Tries Desperately to Win An Award”

Oscar Nunez is TV sitcom royalty at this point, thanks in large part to his iconic role as Oscar in The Office. The actor makes a cameo in season 9, episode 3, “The Gang Tries Desperately to Win An Award,” as the Sudz Manager. In the episode, the gang tries to improve the bar’s customer service after years of neglect, though Paddy’s Pub ironically only ends up somehow getting a worse reputation.

Nunez brilliantly plays into the clean-cut, by-the-book character he has become known as in the past two decades, and it’s almost like a sitcom crossover and as if The Office’s Oscar went on to become a bar manager. Nunez has also appeared in Zoey’s Extraordinary Playlist (as De. Tesoro), Mr. Iglesias (as Assistant-Principal Carlos Hernandez), 3Below: Tales of Arcadia (as the voice of Sergeant Costas), and People of Earth (as Father Doug).

6 Guillermo Del Toro As Pappy

“The Maureen Ponderosa Wedding Massacre.”

It’s only natural that Guillermo del Toro, the director of dark horror fantasy movies like Pan’s Labyrinth and Hellboy, stars in the only It’s Always Sunny in Philadelphia episode that deals with zombies, season 8, episode 3, “The Maureen Ponderosa Wedding Massacre.” Del Toro plays Pappy McPoyle in It’s Always Sunny, and the episode is a horror parody where the gang crashes a wedding.

Pappy initially tries to warn the gang about the looming zombie invasion. However, his tendency to rant and speak gibberish makes him seem crazy (that is, until the zombies actually did invade). The character was popular, so Del Toro returned for another episode appearance in the season 11, episode 7 episode, “McPoyle vs. Ponderosa: The Trial of the Century.” This time around, Pappy is a witness in a trial and he has some key evidence — which is a bird hiding on his head under his hat.

5 Judy Greer As Ingrid AKA “Fatty Magoo”

“The Aluminum Monster vs. Fatty Magoo”

Judy Greer is one of the most recognizable faces on TV, as she’s starred in almost everything. She’s most well known for her role as Kitty Sanchez in Arrested Development, but she’s also had stints on Californication, Royal Pains, Modern Family, House MD, ER, and Two and a Half Men. In It’s Always Sunny in Philadelphia season 3, episode 5, “The Aluminum Monster vs. Fatty Magoo,”

Greer plays an outcast from Dee’s high school days, and they unsurprisingly lock horns when Dee learns Ingrid has become way more successful than her. The story is that she used to be known as Fatty Magoo, but she has now lost a lot of weight and has become much more successful than Dee ever hoped to become. This caused huge problems as Dee is very jealous, despite Ingrid saying she became successful because Dee motivated her in school. She also returned in season seven.

4 Dolph Lundgren As Thunder Gun

“Thunder Gun 4: Maximum Cool”

Action movie icon Dolph Lundgren’s It’s Always Sunny guest role hilariously leans into his past as an action hero in macho movies. In the season 14 episode, “Thunder Gun 4: Maximum Cool,” the gang watches a test screening of the titular fictional movie, which is part of a franchise that has been spoken about so heavily in Always Sunny. However, for the first time ever, viewers actually get to see clips of a Thunder Gun movie, and Thunder Gun is played by none other than Lundgren.

Lundgren is one of the best It’s Always Sunny guest stars, as it’s such a clever piece of stunt casting given what the actor’s known for. It seems amusing to think that Lundgren would go for a role like this. However, he has always been open to mocking himself on screen, and this was par for the course for the Swedish-American actor who got his biggest break playing the evil Russian Ivan Drago in the Rocky franchise. Most recently, he appeared in the DCU as one of the sea kings in Aquaman.

3 Colm Meaney As Charlie Shelley

“The Gang’s Still in Ireland,” Dee Sinks in a Bog”

It’s Always Sunny in Philadelphia season 15 is one of the very few times the series has broken its formula, as the last four episodes are serialized and all set in Ireland. Two of those episodes see Charlie meeting his estranged father, Charlie Shelley (Colm Meaney), for the first time ever, and they get along exceptionally well. That’s until Charlie realizes his dad is neglectful and mean and decides to kick his dead body off a cliff.

The Irish actor has appeared in many movies and TV shows, but he most notably played Chief Miles O’Brien for 12 years in both Star Trek: The Next Generation and Star Trek: Deep Space Nine. On television, he has appeared in Hell on Wheels as Thomas “Doc” Durant, Will as James Burbage, and movies like Tolkien, Marlowe, Law Abiding Citizen, Layer Cake, and Con Air.