It's Always Sunny in Philadelphia is currently the longest-running sitcom in TV history, and it seems there is no sign of slowing down. Showrunners and stars Rob McElhenney, Glenn Howerton, and Charlie Day have all devised a show all about the worst and most cynical people humanity has to offer.

The show can be appalling, shocking, and controversial, but that hasn't stopped the creators from tackling taboo subjects, social issues, and current events, and making it as hilariously twisted as possible. Many episodes made us think, "How did they let that slide!?"

Charlie Bites Santa Claus

Season 6, Episode 13: "A Very Sunny Christmas"

Always Sunny Bites Santa

To get us in the holiday spirit, it's only fitting that Season 6's "A Very Sunny Christmas" is also maybe the darkest and most shocking episode of the series to date, intensified further by one of the series' only uses of uncensored profanity. Don't be alarmed, though, this isn't the only time it'll be on this list. In this episode, Dennis (Howerton) and Dee (Kaitlin Olson) try to pull a Christmas Carol on Frank (Danny Devito) to get him to apologize for his nasty Christmas behavior when the two were children while Mac (McElhenney) and Charlie (Day) try to spread the Christmas cheer across Philly. Upon finding out that his mother had "encounters" with multiple men dressed as Santa when he was young and… well, this was a hard pill for Charlie to swallow.

At the mall, Charlie finds a mall Santa and approaches him. After maniacally asking Santa if he slept with his mom, Charlie bites a bloody hunk of flesh out of him, much to the shock and dismay of children across the mall as Charlie throws out obscenities at Santa. This sequence is violent and profane, probably one of the series' most intense and darkly-hilarious scenes. A perfect holiday episode!

Charlie and Mac Beat Up a Group of Kids

Season 13, Episode 5: "The Gang Gets New Wheels"

Mac and Charlie Beat Up Kids

Violence towards adolescents is already a very shaky and controversial subject, but Always Sunny manages to tackle the subject with hilarious absurdity and sick enjoyment. When a group of kids steals Mac's bike, Mac and Charlie try to be the bigger men and kindly demand to have their bike back. This is to no avail, however, as both the children and the thief's father (Mac and Charlie's childhood bully who also stole their bikes) deny these accusations. With no other options, they decide to retaliate against them.

These children are punched, thrown, and kicked with cheery music playing. The sequence begins with a slow-motion shot of Mac slugging one of the kids across the face, blood spitting out the mouth. Certain they killed at least one of the kids, Mac and Charlie escape the scene of the crime. The on-screen violence is obviously played for laughs and no actual children were harmed but is still an appalling scene of on-screen violence.

Charlie's Mom Fakes Cancer For Profit

Season 8, Episode 6: "Charlie's Mom Has Cancer"

Charlies Mom Has Cancer

"Charlie's Mom Has Cancer" is a reference to the Season 1 episode "Charlie Has Cancer," where Charlie fakes cancer to get The Waitress' (Mary Elizabeth Ellis) attention. That in of itself is despicable but doesn't hold a candle to "Charlie's Mom Has Cancer," as Charlie's mother attempts to raise money to pay for the damage she caused to the church's Virgin Mary statue she accidentally ran over. Cancer donations were clearly the best way to cover that, apparently.

Charlie asks her why she would lie about such a thing. She answers that question in the best way anyone could: "I learned it by watching you." Like mother, like son.

Frank's Couch Birth

Season 6, Episode 13: "A Very Sunny Christmas"

Franks Couch Birth

Another moment from "A Very Sunny Christmas," this time putting a spotlight on Frank Reynold's (see: Danny DeVito's) full-body nudity. Dennis and Dee attempt to Christmas Carol Frank, this time putting him in a couch so he can overhear his former employees' distasteful words about him.

The former Batman Returns star has not been shy about sharing all the crazy stunts he had to perform, from the humiliating to the life-threatening. This couch stunt, in particular, involved DeVito stripping nude, being sewn inside a leather couch, and forcing his way out of it in the middle of a cocktail party, drenching in sweat. This particular scene is one of the series' most infamous and iconic moments to date, one of a multitude that involved putting DeVito in humiliating danger.

The Fake Baby Funeral

Season 7, Episode 4: "Sweet Dee Gets Audited"

Fake Baby Funeral

"Dead baby jokes" are the most tasteless jokes out there, so of course it's a topic that Always Sunny has touched on multiple times. Perhaps the most blatant and brutal of these jokes, however, is when the Gang sets up a fake baby funeral to get the IRS off their backs. The scene is twisted enough, but the series of events makes it incredibly viler and morbidly hysterical.

The funeral is staged at Paddy's Pub, Dennis blows chili powder all over Dee to make her cry but instead makes her eyes bleed, Frank gives a eulogy about his scam Wolf Cola, and Mac and Charlie, onto Frank's schemes, flips the coffin over which they believe is full of rocks but dumps out a dog's carcass instead. Understandably disgusted, the IRS agent tailing them leaves them be. A disgusting but beautiful scene, this is one of the series' greatest attempts to push the limits.

Charlie Mutilates Himself

Season 13, Episode 6: "Charlie's Home Alone"

Charlies Home Alone

Always Sunny is known for pushing boundaries and not being shy about its showcase of violence, and this episode takes that cake. In a two-part episode where Mac, Dennis, Dee, and Frank go to the Superbowl, they accidentally leave Charlie alone at the bar, an obvious parody of the 1990 Christmas classic Home Alone. After the Home Alone-style montage, the episode further cements the spoof by Charlie setting up traps after believing there will be intruders. The traps would be certain death for the so-called intruders, a series of tripwires, paint cans, and even a bear trap.

Surprising nobody watching this, Charlie steps into his own bear trap, ensnared by his own contraptions. Charlie cauterizes the wound but passes out for an entire day. Per his Philadelphia Eagles ritual, Charlie eats a rat, drinks paint (after the cans fall on him), as well as his urine, and continues to fall into his traps as he makes his way across the bar. This episode is so over the top that it reaches a point of being actively disturbing and gross, but what else can you expect from this show?

Mac Feeds Dennis His Dog

Season 11 Episode 5: "Mac & Dennis Go To The Suburbs"

Mac Feeds Dennis Dog

In one of the very best episodes of the show, the show takes a cue from The Shining as we see Mac and Dennis slowly go stir-crazy after moving to the suburbs. Dennis' sanity is dwindling as he deals with a traffic-filled commute, work, and eating the same "MAC-and-cheese" day after day. Meanwhile, Mac is in a depressed state of boredom and loneliness at home, even neglecting to feed the dog Dennis gave him. In a surprising turn of events, the dog dies and is buried in the front yard, much to the numbness of Dennis.

As Mac and Dennis force down another helping of the Mac-and-cheese, secrets, and lies are exposed as the two just can't stand each other any longer. In a shocking confession, Mac admits he put meat hunks in Dennis' meal: the meat of Mac's dead dog. The episode builds up to a moment where Mac and Dennis are ready to go after each other's throats, and revelation with the dog makes the intense scene all the more brutal, as it is laughable.

The Decline of Rickety Cricket

All Seasons, All Episodes

Rickety Cricket Before and After

The Gang is no stranger to ruining the lives of everybody they've ever come across; Bill's affair with Dee crushed his marriage, "Psycho" Pete had to go through rehab because of false rumors spread about him by the Gang, and The Lawyer had his eye injured during a courtroom mishap. But the person that probably fell the most from grace was none other than Matthew Mara, or Rickety Cricket (David Hornsby).

Cricket was a kind and humble priest who retained his high school crush on Dee. He quit the priesthood to marry Dee, but she only flirted with him after Frank insinuated she couldn't get him to bless a Virgin Mary stain in the bar, ruining his life. Throughout the series, Cricket quickly became homeless, got coerced into hard drugs by Charlie, is hunted for sport by Mac and Dennis, has his throat slashed by Frank, becomes horribly burnt and disfigured at the Gang's Thanksgiving dinner, and it goes on and on.

Naturally, the Gang takes no responsibility for all the awful things that have happened to Rickety Cricket. Dennis elaborates by calling him a monster and that he was just "born that way". Despite all these immoral and illegal wrongdoings done to him, Rickety seems to prefer his new life and remains friends with the Gang. As shown in the episode "A Cricket's Tale," he gives up the company of his father, throws away his identity as Matthew Mara, and remains as Rickety Cricket. Is that wrong? Well, at this point, what else would you expect from the Gang?

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