16 Things You Didn't Know About It's Always Sunny in Philadelphia

You may have heard about kitten mittens, milk steak and bird law, but here are a few facts from It's Always Sunny you might not know.

Danny Devito in It's Always Sunny in Philadelphia

It's Always Sunny in Philadelphia fans rejoice! FXX's long-running comedy series has finally debuted its anticipated 12th season, and to surprisingly hilarious results. The mere fact that a show as comically twisted as this has lasted this long and remained just as fresh is nothing short of a miracle. For 11 seasons now, It's Always Sunny has been constantly pushing the envelope when it comes to how depraved and politically incorrect they can get on television, picking up a sizable fan base along the way.

We've watched 'the Gang' get into schemes about solving the gas crisis, taking advantage of welfare, selling kitten-mittens, and putting on a full blown musical production titled "The Nightman Cometh" over the years. Though most fans can sing "Dayman" note-for-note, there are plenty of things behind the scenes of It's Always Sunny that you might not know about. The next 15 items on this list are tidbits of trivia about everyone's favorite depraved group of bar-owners who have bashed apart rats, and swept away our hearts.

Here are 16 Things You Didn't Know About It's Always Sunny in Philadelphia.

16 It's the Longest Running Live-Action Comedy Series

It's Always Sunny in Philadelphia season 12 premiere cast shot

Though they've broken boundaries with their kitten-mittens and milk steak, It's Always Sunny is also marking milestones in TV history. Earlier this year when the long running FX series was renewed for two additional seasons, 14 total, it became the longest running live-action comedy series of all time. It is now tied with Ozzie & Hariet, a comedy-variety program that was broadcasted in the U.S. in the 50s and 60s. The closet live-action comedy series that comes close is Two and a Half Men, which lasted for twelve seasons while runners up include Cheers, Fraiser and Happy Days, which all lasted eleven seasons.

Though the gang has had their share of misfires in each season, the show's quality is just as consistent as ever, as evident in the recent season 12 premiere. It's Always Sunny has proven to continually push the envelope, and it doesn't seem they're going to stop anytime soon. In an interview with IMDb, Danny DeVito said, "We love doing it. As long as fans will have us, FX will do it until we're taken off the planet by some alien force." That's good news for fans, and not a bad pitch for a future episode down the line.

15 Real Life Romances

Charlie and the Waitress animated

You might not be able to tell from their dynamic on the screen, but many of the actors on It's Always Sunny are real life couples. You may already know that Charlie (Charlie Day) and the Waitress (Mary Elizabeth Ellis) are happily married in real life, despite their rather tumultuous relationship on the show, which usually consists of Charlie stalking the Waitress and ruining her life. Though they frequently work together on It's Always Sunny, the couple first met on another TV comedy, Reno 911, with the two playing incestuous twins, which is a little creepy in hindsight.

Even odder than Charlie and the Waitress being an actual couple might be the thought of Mac and Dee getting together, who are quick to berate each other with Mac usually lambasting Dee for looking like a bird and Dee frequently slamming Mac for his karate. In real life their attitudes are the furthest thing from the truth. Rob McElhenney (Mac) and Kaitlin Olson (Dee) have been married since 2008 and have two children, one of whom made an appearance on the show in the episode "Dee Gives Birth."

Finally, though Dennis may be a psychopathic misogynist, that doesn't mean Glenn Howerton is. In real life, Howerton is married to actress Jill Latinao, who you may recognize as the poor pharmacist whose life Dennis ruins in the episode, "The D.E.N.N.I.S. System." Let's hope Howerton didn't use that infamous system to get his bride in real life.

14 The Pilot was Shot for Under $100

Charlie Has Cancer Always Sunny Pilot

If you're a struggling actor/writer who is down on their luck, you only have to look to the humble beginnings of It's Always Sunny in Philadelphia to become inspired. Before hitting it big, creator Rob McElhenney was working as a waiter in L.A. and living out of a garage (Charlie Day would tell you that it was a guest house). In an act of desperation, McElhenney wrote a script about an exchange between two people, in which one tells the other that they're dying of cancer, with the other trying to get out of the room as fast as possible.

What started out as a writing exercise turned into a short film starring McElhenney, Charlie Day, and Glenn Howerton, who had all been friends for years at that point. The majority of the film was shot at the actors' apartments using no professional sound or lighting. Though the legend is that the film was made on a budget of $200, it was actually made for less than $100, with Howerton admitting that it could have cost as little as $85. It was with that pilot that the trio was able to pitch the idea to FX, which just goes to show how far you can really take a shoe-string budget.

Part of the original pilot can be seen on YouTube here.

13 Danny DeVito Became Involved Because His Kids Were Fans

Danny Devito in It's Always Sunny in Philadelphia

Though Frank usually bails the gang out of jams in the show, Danny DeVito being cast as Frank Reynolds is really what saved It's Always Sunny in Philadelphia from going under in the first place. While it's now the longest running comedy series, it never would have gotten to that point without DeVito signing on for season 2. After the show failed to net a core audience in season 1, the network told the creators that they would have to bring in a big name to the cast if there was any hope of continuing.

Enter Danny DeVito, whose name was suggested as a possibility by one of the executives at FX. The actor first became aware of the show because his children were such big fans. After sitting down with McElhenney, DeVito agreed to guest star for season 2, and enjoyed the production so much that he became a regular cast member. Fans of the show really have to thank DeVito's kids for convincing their dad to check out It's Always Sunny, without whom we wouldn't have rum ham, toe knife or the troll toll.

12 Why Glenn Howerton is Named Dennis

Glenn Howerton and Rob McElhenney in It's Always Sunny in Philadelphia

Co-creator Rob McElhenney brings a lot of his real life experiences to It's Always Sunny in Philadelphia. For one, Sweet Dee was actually the name of one of his past girlfriends, and the creepy McPoyle family is based on a real life family he knew from growing up in Philly. McElhenney even uses a variation of his name for his character Mac (although his real name is Ronald McDonald, much to the character's chagrin). Co-star Charlie Day also uses his real life name for the show's dyslexic janitor, Charlie Kelly.

Unlike his co-stars who are named after themselves, fans often wonder why Glenn Howerton doesn't use some variation of his own name in the show, a fact even more surprising considering his name in the original pilot is "Glenn." Howerton has revealed in interviews that his name on the show is Dennis because he wanted to distance himself as far away from the character as much as possible. With Dennis Reynolds becoming more psychopathic as each season goes by, including his twisted sexual memoirs, his tools of duct tape and zip ties, and that creepy "implication," we understand where the actor is coming from.

11 It's Always Sunny in Moscow

It's Always Sunny in Moscow

The antics of It's Always Sunny in Philadelphia have now spread well beyond Philly, and has even crossed the boarders of other countries. There is now a Russian version of the FX series, and even though it might sound as preposterous as a "toe knife," it's true. The spinoff is appropriately named It's Always Sunny in Moscow, with the Dennis, Mac, Charlie, Dee and Frank characters getting Russian makeovers. It's still about four selfish friends and one old man and their tribulations while running their bar, which instead of being named "Paddy's Pub" is named "Philadelphia" as a homage.

Even though the show is an almost shot-for-shot remake of the American version, even to the way shots are framed, the subject matter just doesn't translate to Russian audiences. Some of the plotlines like "The Gang Gets Racist" and "Gun Fever" are only humorous because of the context for western audiences. It just shows that when it comes to playing "night crawlers" and practicing "bird law," it's best to leave it up to the original gang from Philly.

10 Why Mac Got Fat

Fat Mac in It's Always Sunny in Philadelphia

Most great actors are willing to lose or gain weight for their roles, but Rob McElhenney took that philosophy to whole new levels in 2011. When season 7 of Always Sunny hit television screens, fans were taken aback by the drastic increase of weight from the actor, who had gained a whopping 50 pounds in just six months. While his character Mac makes the excuse that he has gotten heavier as a way to "cultivate mass," the actor's actual motives were simply to be funny and prove a point.

It's Always Sunny in Philadelphia is all about breaking down sitcom conventions. One of the things McElhenney had noticed in almost every sitcom is that characters always get better looking as the seasons progressed. As the budget was increased for successful shows more attention was spent to the stars physical appearances, meaning bigger budgets for makeup and physical training staff. McElhenney decided to mock these other shows and take advantage of his character's vanity by gaining 50 pounds in six months, which he achieved by eating five 1,000 calorie meals a day! Though the actor has since lost all the weight he put on, fans will fondly remember the season where a garbage bag of Mexican foods were carried around by "Fat Mac," a term coined by McElhenney's costar, Glenn Howerton.

9 "RCG" Productions Secret Messages

RCG Productions

Every episode of It's Always Sunny in Philadelphia ends with some sort of confusing piece of backwards audio, provided by the show's production company, RCG (formerly RCH). The messages are recorded by the show's creators themselves (Rob McElhenney, Charlie Day and Glenn Howerton), with a new phrase for each season. If you've ever wondered what the messages actually say, you're not alone. Various fans have played the hidden messages in reverse trying to decode what the hidden messages.

Although each season has its own message, many of them involve the word "brown." The season 2 message is "Is a brown, is a brown, is a brown," season 5 is "Next stop - brown town" and season 6 is "BROWN - now in HD." Though the creators have an inexplicable fascination with the word "brown," they do occasionally switch it up. The first season's secret message is Glenn and Charlie saying "You're stupid for playing this backwards," and the Christmas special episode has McElhenney saying, "Sorry for wasting your time and money, but thanks for the money."

A video decoding the first 9 seasons can be seen on YouTube here.

8 Kristen Wiig was Almost Sweet Dee

It's Always Sunny in Philadelphia with Kristen Wiig

It's hard to imagine anyone besides Kaitlin Olson playing Sweet Dee, so you might be shocked to learn that the role almost went to somebody else entirely. Besides being one of Saturday Night Live's biggest stars and one of the newest Ghostbusters, comedian Kristen Wiig was almost part of the Always Sunny gang. According to Glenn Howerton, Olson and Wiig were neck-and-neck in the race for the role of Sweet Dee, but in the end Olson beat out her competition.

Funny enough, Olson almost turned down the part afterwards. Once aboard, Olson realized that the part she read for were actually lines taken from Dennis's character, with Dee playing more of the straight persona for the rest of the material. Rob McElhenney told Olson that he didn't really know how to write for women, but Olson responded by telling McElhenney and the rest of the writers to just write her as they would anyone else, which led to Sweet Dee becoming one of the raunchiest women on television. Even though Wiig had ultimately lost the part to her peer, she didn't make out too shabby either, joining the primetime players on SNL the same year It's Always Sunny debuted.

7 The Guest Stars

Its Always Sunny in Philadelphia guest stars

Like any good show, It's Always Sunny in Philadelphia is not without its fair share of guest stars. The talent that has popped up on Always Sunny has ranged from bigtime actors to professional athletes. Funnyman Keegan Michael Key of Key & Peele played the host of "Family Fight," a gameshow the gang goes on that clearly satirizes Family Feud. Rapper and business tycoon P-Diddy, aka Sean Combs, has also made an appearance on the show as a bass playing doctor, and crooner Josh Groban shows up in one of Sweet Dee's extended fantasy sequences. Actors like Tom Sizemore, Dax Shepard, Sinbad and musicians like Rob Thomas and Kings of Leon have also made appearances in various episodes.

However, some guest appearances are harder to spot than others. You might be surprised to learn that Christopher Lloyd of Back to the Future fame has lent his talents to the Always Sunny crew, hiding behind a white beard while paying a visit to Charlie's prostitute mom in "A Very Sunny Christmas."

Even harder to recognize is director Guillermo Del Torro's brief cameo in the season 8 episode, "The Maureen Ponderosa Wedding Massacre." It's so quick you may have missed it, but Del Torro plays the McPoyle clan's patriarch, Pappy McPoyle. Charlie Day explained that after starring in Pacific Rim, the director let it slip that he was a bigtime fan of It's Always Sunny. On a whim, Kelly emailed the director asking him if he wanted to do a cameo for the show, which Del Torro jumped at the chance to do. The fantasy director even did some of his own makeup for the McPoyle character, including a glass eye, providing one of the funniest and perhaps creepiest cameos in all of Sunny history.

6 Rob McElhenney is Passionate About Gay Rights

Mac and Frank in It's Always Sunny in Philadelphia

It's been a running joke throughout It's Always Sunny that Paddy's Pub's ultimate cooler, Mac, is secretly gay and unwilling to accept it. Between having sex with transvestites and hanging out in gay clubs, Mac is clearly, as he would put it, "into dudes." Mac frequently bashes homosexuality, using any excuse he can to bring up Christianity and the fact that it frowns upon gays who will, in his view, burn in hell for all eternity. Of course, It's Always Sunny likes to point out the way society acts ridiculous sometimes, Mac's warped views on homosexuality and religion included.

On the contrary, Rob McElhenney, who plays Mac, has stated that gay rights are very important to him. The co-creator of It's Always Sunny was partly raised by his mother and her gay partner. The actor's brother is also gay. In an interview with IMDb, McElhenney jokes, "We are one of the gayest families in the northeast corridor. Somehow I was led astray, and I’m heterosexual." In the summer of 2016, most of the cast of It's Always Sunny marched in the L.A. Pride Parade, with each cast member stating what an honor it was to be included. Now, if only Mac could get onboard.

5 Danny DeVito Almost Drowned Shooting Season 11

It's Always Sunny in Philadelphia The Gang Goes to Hell

Though they're known for their outrageous humor and politically incorrect banter, the cast of It's Always Sunny in Philadelphia have also performed their fair share of stunt work. Kaitlin Olson for one has insisted on doing her own physical stunts, which have included getting hit by a car and falling through floor boards. The actress has paid a hefty price however, breaking her foot, back and heel in the process.

Olson is not the only cast member who has gone out of their way to perform some dangerous stunts. During an interview on Conan, Charlie Kelley opened up about working with Danny DeVito, citing one instance where the cast "almost killed him." In the finale of season 11, an underwater sequence was filmed with the characters submerged several feet below. Kelley states that the 72 year old actor is incredibly buoyant, so DeVito had to be weighted down in order to film the shot. When the cameras stopped rolling, the cast members quickly made it to the surface, all except DeVito. Kelley states that DeVito struggled to submerge, flailing about and going nowhere. Thankfully there were safety divers there who helped the veteran actor to the surface. Thank goodness they were there, as the episode would have almost been titled "The Gang Kills Frank."

4 The Cast Knows How the Show will End

It's Always Sunny in Philadelphia Season 10

Or at least some of them do. Glenn Howerton has said that he has known from the beginning what the end of It's Always Sunny in Philadelphia will look like, while Kaitlin Olson has said during an interview with IMDb about the ending, "I know pieces. My husband (Rob McElhenney) likes to keep me in the dark. It's a fun thing we like to do." Despite the actress only knowing certain parts, it seems that the showrunners have at least got a basic idea of what the endgame of Sunny will look like.

Depending on who you ask, comedy shows don't have the best track record when it comes to series finales. Seinfeld  is often cited as the blueprint to It's Always Sunny, but its finale was generally considered disappointing by fans, which ended with all of the principle characters going to jail for all their misdeeds. Will It's Always Sunny in Philadelphia's finale end with the gang finally coming to terms with all the horrible acts they've committed? Will Charlie finally get together with the Waitress? Will Dennis be revealed to be a psycho killer? Will Mac finally admit he's "into dudes?" It's hard to say, but with the creators stating they already have an idea for the gang's swan song, you can rest assure it will provide some huge laughs at the very least.

3 Originally Titled "It's Always Sunny on TV"

It's Always Sunny in Philadelphia cast

As previously mentioned, It's Always Sunny started from humble beginnings with a pilot made on the shoe-string budget of less than $100. After pitching the footage to various networks, the creators finally struck a deal with the executives at FX, who were enticed by the fact that the pilot was cast extremely well. Funded by FX, a new pilot was shot that was strikingly similar to the look of the original, but with a few obvious changes. For one, the story originally revolved around three friends who were all actors living in Los Angeles, and was titled "It's Always Sunny on TV."

According to McElhenney, the fact that the characters were actors wasn't integral to the story. When the network told the creators they didn't want to do another show about struggling actors that was set in L.A., McElhenney came up with the idea to have the characters run a bar in Philadelphia instead. FX was delighted with the idea, and It's Always Sunny in Philadelphia was born.

2 The Cast Never Drinks On Set

It's Always Sunny in Philadelphia high school

For a show about five raging alcoholics who are rarely seen without a beer in their hand (or a soda can filled with wine), you might be surprised to learn that in actuality the cast on It's Always Sunny NEVER drink while on set of the show. In a 2009 interview with Collider, Rob McElhenney talks about a scene he was shooting with Danny DeVito, stating that his co-star and the rest of the actors all drink a kind of fake beer. Glenn Howerton was also asked on an AMA on Reddit if the cast really drinks on set, responding with: "'We NEVER drink on set. It's "bad for insurance" and we would NEVER want to put the show at risk.... NEVER!!!!!."

Though some hardcore fans might be bummed that the gang isn't as sloppy as they thought, it truly is a testament to the actors' talents that they can convincingly come off as drunk as they appear (especially Charlie Kelly and Kaitlin Olson). It's also reassuring that the crew would never put the show at risk by getting a little tipsy before shooting an episode. It's probably better to play a hardcore drinking game like "Chardee MacDennis" after the cameras stop rolling anyway.

1 It's Always Sunny on Game Of Thrones

Game of Thrones and It's Always Sunny in Philadelphia

It's a known fact that Rob McElhenney is a diehard fan of HBO's Game of Thrones, even interviewing the entire cast during a 2013 Emmy Panel (before giving each of them an ocular patdown of course). But did you know that the Game of Thrones creators are just as crazy about It's Always Sunny in Philadelphia?

Thrones showrunners David Benioff and D.B. Weiss are longtime Sunny fans, and after admitting the fact to McElhenney they were invited to write an episode which they gladly did. The pair wrote the season 9 episode "Flowers for Charlie," which satirizes the famous novel Flowers for Algernon, in which a slowwitted man has his intelligence increased by artificial means. The story is adapted by Benioff and Weiss for Charlie's character, who naively thinks he is made smarter by ingesting nothing but a placebo pill. It leads to hilarious results, with Charlie inventing a harebrained contraption that he believes has the capacity to allow spiders to talk with cats.

Rumor has it that in exchange for penning an episode, Benioff and Weiss offered the Always Sunny cast to appear in an episode of Game of Thrones when the moment is right. If that's true, than we just found another reason to get excited for season 7. If there's anyone who can outdrink Tyrion, a man who drinks and knows things, it's definitely the Always Sunny crew, who drink and don't know anything.

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