It's Always Sunny In Philadelphia Season 15 Ending Explained: The Gang Are America, Sweetheart

With 15 seasons under its belt, "It's Always Sunny in Philadelphia" is now the longest-running live-action comedy series in American television history. The season finale of the record-breaking fifteenth season aired in December, capping off the series' longest-running single arc following the gang on their vacation in Ireland for four full episodes. While there have been several two-parters in the series' history, they've never done something quite this ambitious, and it paid off in spades. "It's Always Sunny in Philadelphia" is as sharp as ever, and though the team making the show has grown and changed over the years, the gang has proven they will always stay the same. 

While the first few episodes of the season helped explain a bit more about the gang's past, the Ireland arc will help define their future. A lot happened in those four episodes, so I'm going to break down the why, how, and what happened of it all, like Artemis dissecting the mystery of who pooped the bed. Season 15 of "It's Always Sunny in Philadelphia" was full of weird moments, throwbacks, and unanswered questions, so let's see if we can make a little sense out of the madness. 

Spoilers ahead for season 15 of "It's Always Sunny in Philadelphia." 

Each of the episodes that take place in Ireland starts with a cup of stew, which the gang seems to believe has some kind of restorative purpose. In "The Gang Goes to Ireland," they try to wake a hungover Dee (Kaitlin Olson) by putting stew under her nose, then they do it again in "The Gang's Still in Ireland." In "Dee Sinks in a Bog," she throws hot stew in Dennis' (Glenn Howerton) face to wake him up in his hospital bed, post-Covid scare. Smelling the stew didn't seem to wake Dee up, but launching it in someone's face tends to do the trick. In "The Gang Carries a Corpse up a Mountain," things finally make a bit of sense when the gang begins their day by eating some stew instead of sniffing it or chucking it at their sibling.

Why does the gang think stew wakes people up? Stews and soups have been associated with healing and recovery for a long time, and friends often bring one another chicken soup if they're feeling ill, so maybe they just took it a step farther? There's really no telling with the gang because most of their preconceptions about the world come from pop culture and not reality. They probably saw it on TV one time and now believe that stew works like smelling salts. Everyone except for Dennis, of course, who is skeptical of all things including vaccines. 

In season 15, Charlie (Charlie Day) finally meets his biological father, Shelley Kelly (Colm Meaney). Charlie's paternal parentage has been a mystery over the course of the series, as his mother Bonnie (Lynne Marie Stewart) is pretty promiscuous. For a long time, it looked like Frank (Danny DeVito) was Charlie's dad, though the two men did once get married in order for Charlie to share in on Frank's health insurance. They've also had some sexual experiences together, so at this point, it's probably a really good thing that Frank isn't Charlie's father, and it was nice to see Charlie finally feel loved and understood. 

In a cruel twist of fate, Dennis passes his Covid onto Frank, who also didn't get vaccinated. He told the gang that he did, but his form of "a vaccine" was actually taking a bunch of the various remedies touted by conservative pundits, including horse dewormer. Frank only ever had mild symptoms, but he passed the virus onto Shelley, who died gasping for air. Charlie had planned on staying in Ireland with Shelley, learning to be a cheesemonger under his father's tutelage, but Frank accidentally put an end to that by killing him. 

Charlie agrees to carry on the family's burial tradition by carrying his father up a mountain and launching him off into the ocean, but since this is "Sunny," things don't exactly go as planned.

This one's a toughie because the series has always skirted around whether or not Dennis is actually capable of murder. Though he was exonerated of any wrongdoing in the death of his ex-wife, Maureen Ponderosa (Catherine Reitman), there have since been hints that Dennis may have had something to do with it. In "The Gang Carries a Corpse up a Mountain," Frank reveals that Dennis is likely responsible for at least one other death. 

After Dennis recovered from Covid in the hospital, Dee set up a date with a hot doctor (Tom Archdeacon), telling him to meet her back at the castle she's renting with Dennis. While carrying Shelley up the mountain, Frank reveals that Dennis might have killed the doctor using a hot oil trap originally planned for Shelley. Dee asks her brother if he used "the murder hole," and he explains that since she "wasn't there to enjoy him," he did instead. It sure sounds like Dennis committed a murder, especially since he says that he had his fun in order to follow "the castle's wishes." That's right, Dennis has been talking to a haunted castle, and he doesn't stop after he's cured of his fever. Let's hope the castle doesn't somehow follow him back to Philly. 

Finding out that her brother at the very least burned her hot date sends Dee into a fury, which is when she decides she doesn't want to help carry Shelley any longer. 

Dennis ends up bailing on helping with Shelley because he's worried about his back, which he claims is "like the Vetruvian Man." Dennis has always been vain and believed he's some kind of golden god, so this tracks. Poor Mac ends up leaving when he discovers that his friends have been selling him an elaborate lie that shook him to his core. In "The Gang Goes to Ireland," Mac called his mom (Sandy Martin) and asked her about their Irish heritage. She tells him that he's not actually Irish and that his real last name is Vandross. This sends Mac into a spiral, as he doesn't know how to reconcile his identity without the Irish bit to balance him out. (The Catholic and gay sides just aren't going to get along, which this season highlights quite well.) While carrying Shelley up the mountain, the gang reveals that Mac is actually Irish and they paid his mom to tell him he wasn't so that he wouldn't brag about being Irish the whole trip.

It's a brutal reveal that retroactively makes the earlier episodes even funnier, and it totally fits with the "everyone hates Mac" trend that has existed since the series started. Mac and Dennis leave, and only Frank is left to try and help Charlie. He offers Charlie some Gatorade and discovers that he accidentally filled both of his water bottles with urine. He had originally planned on having just one piss bottle when he thought Shelley was still alive, just in case he needed to pull one over on his rival. The cruelty and the weirdness sends Charlie into a rage, and Frank heads back with the others, dejected. 

The gang return to Patty's Pub, an Irish pub in the countryside where they've rented a room. While there, they discuss how they never want to see one another again, and they are shushed by the Waitress (Mary Elizabeth Ellis). Dee left the Waitress in a bog after using her to climb out, and now the whole gang is yelling about their personal nonsense in a room full of people. The Waitress has had enough, and she shushes the gang.

There's just one thing: the gang does not like to be shushed. In season 7, the gang spends the entirety of "The Anti-Social Network" trying to find a man who shushed them at a bar, because the fact that he had the audacity to do so enrages them so much. To be shushed by the Waitress, whose name they have never even learned, is another thing altogether. When the Waitress tells them they're not in America, Frank gives a rousing monologue:

"We are America, sweetheart! And we carry our country wherever we go! Because we love her, and when you love someone, you can't bear to leave 'em behind, not ever!"

Throughout the season, the gang has shown their American spirit through and through. They wreaked havoc during 2020, refused to change in spite of evidence that it would be wise to do so, and even brought their country along with them while visiting abroad. It's been a long time since Charlie went America all over everybody's a**, but the gang is still as American as moonshine and apple pie. 

In one of the most heartbreaking sequences in the show's history, Charlie is eventually left to carry his father up the mountain alone. The other members of the gang have each bailed for their own reasons, most of them selfish. It begins pouring rain, and Charlie starts to sob. "You were supposed to carry me!" he shouts at his father's corpse before listing all of the things his father failed to do. Poor Charlie never had a father figure in his life until Frank came along, and the only male figure in his childhood was his Uncle Jack (Andrew Friedman), who probably molested young Charlie. 

Even as an adult, Charlie is at the bottom of the hierarchy — there's a reason that work no one else wants to do is called "Charlie work." Though Charlie occasionally gets the upper hand on others, it's usually all too brief. Seeing the gang's most earnest member bawling in the rain is painful stuff, and Day's performance is brilliant. 

"It's Always Sunny" rarely crosses over from comedy into real dramatic moments, but when it does, it can be truly powerful. 

When the gang first got to Ireland, Dennis rented a tiny European car in an attempt to not be "awful American tourists." They spotted a huge American truck and complained to one another about it, saying that things like that were why people hate Americans. Once the gang embraces the fact that they are awful American tourists, they pay the owner of the big Ford truck to take it up the mountain. Oddly enough, trucks and SUVs have helped the gang save the day a few times, and the reveal of the truck tearing up the Irish countryside is reminiscent of "The Gang Gets New Wheels." In that episode, Dennis needs a replacement for his Land Rover, which was destroyed when he moved to North Dakota. He ends up finding one and picks up the members of the gang as they deal with different transportation issues around Philly. If the gang were horsemen of the apocalypse, their pale horse would definitely be an American gas-guzzler with four-wheel drive.

They toss Shelley in the bed of the truck and then toss him off the cliff, as per his wishes. They might not have completed the task the old Irish way, but they did it their way, just like they do everything.   

The final moments of the season are sweet, as the gang embrace one another and discuss the things they're excited about back in Philadelphia. Unlike the uncertainty at the end of season 14, this season ends on a decidedly hopeful note. 

The gang is looking forward because as long as they have each other, they'll survive. They may be horrible to everyone, including one another, but the gang deserves each other. They're a friend group of the most abrasive kind, with shared trauma, a warped way of looking at the world, and loads of co-dependence. With three more seasons planned at FXX, here's looking to everyone's favorite f***ed up found family for years to come.