Very few television shows are anywhere near as brazen as It's Always Sunny in Philadelphia. Some of the plot lines found throughout the series are seriously messed up and yet many consider it to be one of the best TV comedies of the 21st century. Were it not for its wonderful cast of characters though, that might not be the case.

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Dee, Dennis, Mac, and Charlie are all incredibly dysfunctional human beings with some rather severe emotional and psychological problems to contend with. Frank, on the other hand, is just a senile old man who's looking for a chance to relive his wasted youth. Together, they've shared plenty of wild and inappropriate adventures; the best of which are some of the funniest to have ever appeared on television.

Updated January 15, 2022, by Tom Bowen: Many shows struggle to remain relevant for more than just a few seasons, yet It's Always Sunny in Philadelphia has never really faltered. Its fifteenth season recently finished airing on FX and, rather than getting worse, many fans actually consider it to have been one of the best seasons of the show in years. Given its incredible longevity, it's unsurprising that the network's executives have already renewed the show for at least another three seasons. With a lengthy wait now expected until season 16 begins airing though, fans of the show will have to settle for re-watching the best Always Sunny episodes in order to get their fill of the gang.

22 The Gang Goes on Family Fight (S10E08)

its-always-sunny-best-episodes-s10e08-the-gang-goes-on-family-fight

The eighth episode of season ten sees the gang appear on a quiz-style television show called Family Fight; a clear play on the long-running US show Family Feud and its UK counterpart, Family Fortunes. Sadly, however, their obsession with how they're going to come across to the nation has a huge impact on their performance, as too do some of their strange and downright ridiculous answers.

As the episode unfolds though, it becomes clear that Charlie was one of the 100 people surveyed for the episode, which allows the Reynolds family to steal their way to the final. When Franks somehow scores 195 points and finds all five of the top answers, it begins to look as though their fortunes may have changed, with Dennis only needing to score five points to secure the $20,000 top prize. The duplicate answer buzzer causes him to have a meltdown, however, and the episode ends with the Golden God begging the show's producers not to air it; which, of course, they do!

21 The Gang Goes to the Jersey Shore (S07E02)

its-always-sunny-best-episodes-s07e02-the-gang-goes-to-the-jersey-shore

In their younger days, the Reynolds twins enjoyed many a summer down on the Jersey Shore. When the gang returns many years later, however, it's not at all how they remember it, with drugs, crime, and pollution having completely changed the once charming resort. Dennis and Dee end up having a terrible time as a result, but the same isn't true for everyone.

Charlie ends up connecting with the waitress in ways that he never thought possible and Frank and Mac come up with an ingenious way to get around the shore's strict open container laws. The episode is full of fantastic and memorable moments, like when Dee and Dennis take Charlie down beneath the boardwalk while in search of magic and when Mac and Frank are stranded out at sea.

20 How Mac Got Fat (S07E10)

its-always-sunny-in-philadelphia-s07e10-how-mac-got-fat

Despite claiming to be a devout catholic, Mac doesn't seem to have a great understanding of how the religion actually works. Viewers see this time and time again, but none more so than in the tenth episode of Season 10, How Mac Got Fat, during which he attends confession so that he can tell a priest all about his recent weight gain.

Rather than taking responsibility for his own actions, however, Mac instead blames the rest of the gang and asks the priest to smite them. Though they and their success certainly played a part in Mac's sudden obesity, it is ultimately his own stupidity and his failure to predict his friends losing interest in yet another ridiculous scheme that are to blame for all of his excess mass.

19 Sweet Dee Has a Heart Attack (S04E10)

its-always-sunny-in-philadelphia-s04e10-sweet-dee-has-a-heart-attack

After Sweet Dee has a heart attack, the gang all begin to worry about their health, though each ends up far more unhealthy than they started. Dee and Dennis decide to join a gym to improve their fitness, while Charlie and Mac opt to take an office job that provides health insurance. Being the only one with money, Frank exploits his own health insurance, but ends up losing his grip on reality after mixing prescription meds.

While Dee and Dennis' gym antics are certainly enjoyable (particularly their interactions with the spin class instructor) and Frank's incarceration and subsequent escape serve as a nice distraction, it's Charlie and Mac who steal the show this time around. From Mac's referencing of Yello's "Oh Yeah" to Charlie's now-infamous "Pepe Silvia" rant, they really do provide a laugh every minute and make this one of the best Always Sunny episodes to date.

18 The Gang Makes Lethal Weapon 6 (S09E09)

its-always-sunny-in-philadelphia-s09e09-the-gang-makes-lethal-weapon-6

The Gang Makes Lethal Weapon 6 touches on themes and ideas found in several of the series' previous episodes. Most notably, the quintet's unofficial Lethal Weapon sequels return, though the episode also reintroduces the arguments surrounding sex scenes in movies that were first explored in Mac and Charlie Write a Movie and the large-chested women charts used when the gang was trying to get a loan to buy gasoline back in Season 4.

Though perhaps not as good as the episodes in which these elements first featured, Season 9's penultimate offering is still a funny one, and once again examines what should and should not be considered tasteful on both the small and silver screens. The show's creators save the best until last, however, with Frank's full-penetration scene serving as the perfect punchline.

17 The Gang Turns Black (S12E01)

its-always-sunny-in-philadelphia-s12e01-the-gang-turns-black

Having repeatedly lampooned the practice of using blackface in the past, The Gang Turns Black felt like a logical next step in many ways. The premise itself is a little ridiculous, though it allowed both the gang and the audience to explore the issue of racial prejudice in a humorous yet profound way. It came at a time when the subject matter really needed to be discussed and remains relevant to this day.

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The "What are the Rules?" song that punctuates the episode's key plot lines and ties everything together is funny, but never in a way that could be construed as tasteless. The episode's ending pulls this balancing act off particularly well, though becomes incredibly dark once viewers remember that Charlie's alter ego is a young child.

16 Mac & Charlie Die (S04E05 & S04E06)

its-always-sunny-in-philadelphia-s04e05-mac-and-charlie-die

Though they are technically two separate episodes, Mac & Charlie Die feels more like one extended episode that's been cut in half. In it, Mac and Charlie decide to fake their own deaths after getting on the wrong side of Mac's father, Luther, but it's Dee who ends up paying the price once all's said and done.

The delinquent duo decides to destroy her car as part of their cover story, though not before pulling out some of their teeth for the crime scene investigators. They then end up hiding out on the roof of Paddy's and in the pub's vents, where, among other things, they're able to witness their own memorial service.

15 CharDee MacDennis: The Game of Games (S07E07)

It's Always Sunny in Philadelphia CharDee MacDennis: The Game of Games (S07E07)

The gang doesn't really do things in half-measures, as evidenced by their version of board game night. CharDee MacDennis is a brutal and depraved game with some of the most ridiculous rules and challenges imaginable and yet it somehow manages to remain perfectly in keeping with the gang's usual antics. That is to say, that it's both hilarious and shocking in equal measures.

Frank's naivety at first seems like a bit of a handicap to his new teammates, but it's through his diligence and astute powers of perception that he's able to draw The Leprechauns level. Even with the odds no longer stacked against them, however, Charlie and Mac still end up losing out, with the Golden Geese once again emerging victorious from the game of games.

14 Time's Up For The Gang (S13E04)

It's Always Sunny in Philadelphia Time's Up For The Gang (S13E04)

Much like South Park, It's Always Sunny has never shied away from taking a satirical swipe at topical and highly sensitive issues in its episodes, nor has it ever attempted to gloss over how depraved and inappropriate the gang can often be. The Me Too and Time's Up movements take center stage this time around and once again demonstrate just how out of touch the Paddy's proprietors really are.

The sexual harassment seminar serves as the perfect backdrop against which to remind viewers of just how messed up the gang really is. The episode also reminds viewers that men can also be the victims of sexual harassment and abuse, something that can often be overlooked. Of course, the gang learns nothing from the experience and the whole thing is eventually revealed to be yet another one of Dennis' insane and immoral schemes.

13 The Gang Goes To A Water Park (S12E02)

It's Always Sunny in Philadelphia The Gang Goes To A Water Park (S12E02)

When it comes to overused sitcom tropes, the central characters visiting a water park is definitely pretty high up on the list. It's perhaps understandable why too, given the many opportunities for comedy that such a setting presents. Granted, most of these tend to involve toilet humor, but It's Always Sunny at least tries to put its own spin on things.

Mac and Dee get stuck in a water slide and end up causing a massive pile-up, while Dennis' pursuit of his next potential victim is interrupted when he thinks he's found himself a new protégé. The hilarious climax, which ends with a mad panic to escape from a pool full of Frank's blood serves as a fitting end to a terrible trip, although Mac does manage to sit on a drain during the chaos, which seems to make him happy, at least.

12 Hero or Hate Crime? (S12E06)

It's Always Sunny in Philadelphia Hero or Hate Crime? (S12E06)

There's an argument to be made that It's Always Sunny is at its absolute best not when its characters are acting crazy, but when they're given an opportunity to demonstrate just how warped their mindsets are through their dialog. Like the episode where the gang goes to therapy over some dishes or the time when they hold a mock trial over eating cereal while at the wheel, Hero or Hate Crime? does exactly that.

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During the act of saving Mac from a falling piano, Frank uses a homophobic slur, prompting the gang to ask themselves the titular question. There's also an argument over a winning lottery ticket, as well as the mystery of why Charlie decided to intentionally tread in dog crap. Dennis also sinks to some old lows, this time trying to score points with a 20-year-old coffee shop waitress in the build-up to her 21st birthday.

11 Charlie Work (S10E04)

It's Always Sunny in Philadelphia Charlie Work (S10E04)

Just as the waitress doesn't appreciate all of the strange things that Charlie does for her (as evidenced by the season 8 episode with the Taft family), the gang is completely oblivious to the hard work that Charlie puts into the day-to-day running of Paddy's Pub. Charlie Work paints a pretty clear picture in that regard, although, sadly for him, the gang is too preoccupied with their chicken, steak, and Air Miles scam to even notice.

For Paddy's Pub to pass an inspection on a normal day would likely be challenging enough, but to do so while they're in the middle of yet another ridiculous and illegal scheme seems like the very definition of an impossible task. Against all the odds, however, Charlie is somehow able to pull it off, despite him having to contend with his friends' insane antics and Dee's complete and utter incompetence.

10 The Gang Tries Desperately To Win An Award (S09E03)

It's Always Sunny in Philadelphia - The Gang Tries Desperately To Win An Award (S09E03)

Upon realizing that Paddy's is one of the only bars in Philly to have never won an award, the gang tries to emulate one of their rivals with hilarious and catastrophic results. Charlie has little interest in their endeavors, however, and instead opts to write a special song for the occasion. It's certainly memorable, although perhaps not quite what the gang was hoping for.

Mac's inability to understand even the simplest of concepts and Dee's incessant vanity may have caused a lot of the problems, but none of the gang really come out of this episode smelling like roses. Dennis is his usual neurotic self while Frank's perverse nature yet again shines an ugly light on proceedings. Unsurprisingly, they don't win the award and end up spitting on the judges in order to make them leave.

9 Dennis and Dee Go on Welfare (S02E03)

It's Always Sunny in Philadelphia - Dennis and Dee Go on Welfare (S02E03)

Fed up with being pushed around by Frank, Dennis and Dee decide to quit their jobs and sign up for welfare. Unfortunately, they don't quite meet the criteria and so come up with a scheme to help them game the system. Things don't quite go to plan though and the siblings end up developing a rather nasty drug problem instead.

While the welfare slaves and spending spree subplots each provide some great moments, it's Dennis and Dee's escapades that really make this episode so memorable. Up until this point, their reckless actions had gone more or less unpunished and so to see them having to face some fairly life-changing consequences this time around felt a lot like karma finally catching up with them.

8 The Gang Gets Analyzed (S08E05)

It's Always Sunny in Philadelphia - The Gang Gets Analyzed (S08E05)

One only needs to watch a few episodes of the show to realize that each of the gang has a lot of issues, although it's nice to have them all laid out in just one place. From Frank's first kiss to Mac's issues with his weight, each of the vignettes used to explore their many problems is punctuated with fantastic humor and some wonderfully bizarre revelations.

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That the gang would go to such lengths to determine who has to wash the dishes says a lot about the group dynamic, as too do Dennis' attempts to position himself as a co-therapist of sorts. It does all work out in the end though, with everybody but Dee coming away from the therapy session with a smile on their faces.

7 The Gang Solves The Gas Crisis (S04E02)

It's Always Sunny in Philadelphia - The Gang Solves The Gas Crisis (S04E02)

The gang has come up with plenty of get-rich-quick schemes over the years, but none have been quite as memorable as their door-to-door gas sale venture. Armed only with Dee's life savings and Frank's creepy panel van, they purchase several trash cans worth of gas in the hopes of flipping it for a healthy profit. Predictably, perhaps, both their plan and the van go up in flames.

It's an episode that's packed with funny moments; from Mac, Dennis, and Charlie attempting to seduce a bank clerk in order to get approved for a loan to Frank's continued obsession with his dead wife's lover Bruce. It all ends with Charlie living up to his wildcard status and Dee once again finding herself severely out of pocket.

6 Mac & Dennis Move To The Suburbs (S11E05)

It's Always Sunny in Philadelphia - Mac & Dennis Move To The Suburbs (S11E05)

After Dee gets fed up with Mac and Dennis staying at her place, the pair end up moving to a little house in the suburbs. What starts out as their dream home though quickly becomes a nightmare and pushes both men to the very brink of insanity. Unfortunately, an ill-conceived bet with Frank means that leaving just isn't an option, and they're forced to stick it out to avoid having to share a bed with Dee and an old man.

The tragic demise of their new dog Dennis is just the tip of the iceberg when it comes to this episode's many messed up moments, but there's plenty of humor sprinkled in there too which serves to break up the darkness just a little. As an added bonus, the old man from the bet goes on to become a semi-regular character in later episodes of the show.

5 Thunder Gun Express (S07E11)

It's Always Sunny in Philadelphia - Thunder Gun Express (S07E11)

With the president in town and the streets of Philly gridlocked, the gang risk missing out on the biggest action movie of the summer. Every avenue they take seems to lead to yet another roadblock, and they're forced to separate along the way. Amazingly, however, they all make it to the movie theater just in time. Well. Apart from Frank, that is; although despite being arrested for stealing a boat, the old man still has one last trick hidden up his sleeve.

Listening to Frank regaling a group of Chinese tourists with tales of the gang's past adventures really does put some of the show's ridiculous episodes into perspective; this one included. What's more, seeing how quickly the gang are willing to abandon each other shows just how selfish and uncaring each of them really is.

4 A Very Sunny Christmas (S06E13)

It's Always Sunny in Philadelphia - A Very Sunny Christmas (S06E13)

While most Christmas episodes are packed full of holiday cheer and feel-good moments, A Very Sunny Christmas is instead one of the darkest and most depressing episodes of the show to date. The gang is all forced to reflect on how crummy their childhood Christmases were, and they ultimately end up getting held up at gunpoint by one of Frank's old business partners.

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That Mac's father is a criminal, Charlie's mom is a whore and Frank is a terrible father isn't really news to the audience at this point. Seeing the true extent of these things is really quite shocking though and goes a long way to explaining why the gang is all as messed up as they are. The episode's highlights include Frank getting sewn naked into a sofa, Charlie attacking Santa, and the gang celebrating Christmas Day by throwing rocks at trains.

3 The D.E.N.N.I.S. System (S05E10)

It's Always Sunny in Philadelphia - The D.E.N.N.I.S. System (S05E10)

Dennis regularly displays sociopathic tendencies throughout the series, whether by taking advantage of "the implication" attached to a situation or demanding that women sign contracts and other legally binding documents. The true scale of his issues doesn't really come to light though until he unveils his foolproof pickup techniques to the rest of the gang.

The Dennis system is problematic on a number of levels and perfectly captures how misguided and manipulative Dennis is when it comes to hooking up with women. That both Mac and Frank each have their own systems for swooping in once Dennis has 'separated entirely' shows that they too are a little clueless when it comes to the opposite sex.