It’s Always Sunny in Philadelphia arrived on the airwaves of FX as a breath of fresh air, because it has a comic sensibility that’s much darker than the average mainstream sitcom. Its principal cast of characters – Dennis, Dee, Mac, Charlie, and Frank – are among the most deplorable, morally bankrupt characters on the small screen, and their exploits often lead them to do truly heinous things.

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It’s Always Sunny tends to take a serious subject, like cancer or abortion (and that’s just the first season), and put a hilarious spin on it by introducing it into the lives of these characters. So, here are The 10 Darkest Episodes Of It’s Always Sunny.

Mac and Dennis: Manhunters (season 4, episode 1)

Always Sunny Dee and Charlie Cannibals

In the season 4 premiere episode “Mac and Dennis: Manhunters,” Frank has been hunting animals and eating their meat. He’s mad that Charlie and Dee have been eating his strange meats, so he tricks them into eating human meat. And then, they find that they can’t shake the craving for human flesh and plot to cannibalize a homeless man.

Meanwhile, Mac and Dennis don’t believe that hunting a defenseless animal is really a challenge, and that the true challenge is hunting a man. So, they set out to hunt down Cricket with the intention of pinning him down and tea-bagging him when they catch him.

Charlie Has Cancer (season 1, episode 4)

Charlie Has Cancer Always Sunny Pilot

The premise of the season 1 episode “Charlie Has Cancer” was used in the cheaply produced short film that the creative team behind It’s Always Sunny used to pitch the show to networks. In it, Charlie tells his friends that he has cancer and they grapple with the news, trying to figure out what they should do with it.

As it turns out, Charlie was lying about the cancer to curry favor with the Waitress, in an attempt to get her to hate him a little less. The premise was later recycled with Charlie’s mom Bonnie in season 8’s “Charlie’s Mom Has Cancer.”

The Gang Goes to the Jersey Shore (season 7, episode 2)

Charlie drinks sunblock on the beach in It's Always Sunny in Philadelphia.

Dennis and Dee are the only ones who actually want to go on a vacation to the Jersey Shore in season 7’s “The Gang Goes to the Jersey Shore,” and they’re the only ones who have a terrible time.

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While Mac and Frank get themselves lost at sea and end up on a yacht with some “guidos,” and Charlie has a magical evening with the Waitress (who turns out to be high on ecstasy the whole time), Dennis and Dee get spiked with angel dust and are forced to take part in an armed robbery. Then, they’re taken down to the beach and forced to bury the corpse of a veterinarian who incidentally became a casualty of the job.

The Gang Finds a Dead Guy (season 1, episode 6)

Death is a tricky subject for comedy. In the penultimate episode of It’s Always Sunny’s first season, “The Gang Finds a Dead Guy,” a corpse shows up in the bar. This prompts Dennis and Dee to visit their grandfather in the nursing home they’ve stuck him in as they grapple with the concept of death.

He turns out to have a bunch of Nazi memorabilia that Charlie has a lot of fun with. One particularly memorable shot sees Charlie opening his apartment door in an S.S. uniform with a half-eaten banana in his mouth and an unsettling smile on his face.

Mac & Dennis Move to the Suburbs (season 11, episode 5)

Mac and Dennis sitting at a dinner table in It's Always Sunny in Philadelphia

Season 11’s “Mac & Dennis Move to the Suburbs” doesn’t have a particularly dark premise: Mac and Dennis rent a house in the suburbs, and if they can live there for a month without cracking, Frank will pay their rent for a year.

However, the mundanity of their new suburban life drives them insane, paving the way for some dark moments. Dennis buys Mac a dog to give him some company during the day while he’s at work, but Mac neglects the dog until it starves to death and then feeds it to Dennis as a cry for attention. It gets really grim, really fast.

The Gang Gets Extreme: Home Makeover Edition (season 4, episode 12)

Glenn Howerton In It's Always Sunny In Philadelphia

In season 4’s penultimate installment, “The Gang Gets Extreme: Home Makeover Edition,” Dee gets the Gang all riled up about “vision boards,” and making your dreams come true by putting good into the world, which she read in a nonsensical self-help book.

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They decide to do some good deeds in the form of a Ty Pennington-esque home makeover for the Mexican family that just moved in down the street, who they dub “the Juarez family.” They break into the family’s house in the middle of the night and drags them out. Due to the language barrier, the family fears they’ve been kidnapped.

A Very Sunny Christmas (season 6, episode 13/14)

The gang singing Christmas carols in It's Always Sunny in Philadelphia

It’s Always Sunny wrapped up its sixth season with a holiday special, aptly titled “A Very Sunny Christmas.” Dennis and Dee make a futile attempt to pull A Christmas Carol on Frank to get him to realize the error of his ways, but he turns out to be even more despicable than Scrooge – or, at least, dumber than Scrooge – because he doesn’t pick up on any of the hints.

Meanwhile, Mac finds out his dad stole all of his childhood Christmas presents and Charlie finds out his mom is a yuletide prostitute. This unhinges Charlie even more and leads him to bite a chunk out of a mall Santa’s face; it’s a bloodbath.

Dennis and Dee Go on Welfare (season 2, episode 3)

In season 2’s “Dennis and Dee Go on Welfare,” Dennis and Dee decide to quit their jobs at Paddy’s to pursue their dreams of being a veterinarian and an actor, respectively. However, they find that it’s harder than they thought it would be and immediately apply to receive welfare.

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They claim to be recovering crack addicts in the welfare office, but they’re asked to present some medical paperwork, so they decide to try a little bit of crack, then visit a doctor and get a medical report, then get the welfare. But they end up just getting hooked on crack.

Pop-Pop: The Final Solution (season 8, episode 1)

Dennis and Dee’s grandfather slips into a coma in the season 8 premiere “Pop-Pop: The Final Solution,” and they’re faced with the decision of whether or not to pull the plug. As they dig out some home movies to get a sense of sentimentality about Pop-Pop, they realize that all throughout their childhood, he took them to white supremacist rallies, where they took part in Nazi chants without realizing it.

Meanwhile, Charlie and Mac chase a painting by Hitler across Philadelphia in the hopes of becoming famous as its discoverers, with a movie getting made about their quest to find it.

Sweet Dee Gets Audited (season 7, episode 4)

Always Sunny Sweet Dee Gets Audited

In this episode, Dennis even admits that it’s “the darkest thing we’ve ever done.” Dee has been collecting financial benefits for the baby that she gave away. When the IRS catches on and comes a-knocking, she avoids them for as long as she can. She tries to get Mac and Charlie to find her a baby to show the IRS that she does have the son that she says she does.

But Dennis realizes that a better solution would be to convince the IRS that the baby is dead, thus getting them off their backs. So, shockingly, they put on a baby funeral.

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