It's Always Sunny In Philadelphia Season 16 Teases Fun References To Earlier Seasons

One of the best things about "It's Always Sunny in Philadelphia" is that with 15 seasons under their belt and a sixteenth on the way, they have a treasure trove of characters and throwbacks to reference and bring back for more hilarity. Sadly we'll never see some of their best guest-stars again (Country Mac, we hardly knew ye), but the season 16 trailer hints at a whole lot of great comebacks and some fun new guest stars. 

We already knew that Bryan Cranston and Aaron Paul of "Breaking Bad" were going to appear in the season thanks to a tweet from creator Rob McElhenney, but now we get to see a bit more about what they're doing, and in the process see that they're bringing back Charlie (Charlie Day) as a limo driver, a callback to the season 7 episode "Frank's Pretty Woman." In fact, there are a load of references to past seasons in the trailer, giving hardcore fans a chance to make theories about the upcoming season and get hyped to see their old favorites. 

Double-check the van brakes, boil up some milksteak, and prepare yourselves to dig deep into all of the magical throwback moments we'll get to see in the upcoming season. "It's Always Sunny in Philadelphia" season 16 premieres on June 7, 2023, on FXX and the next day on Hulu.

Charlie's apartment

Charlie has lived with Frank (Danny DeVito) in squalor in a one-room apartment since season 2, when Frank moved with Charlie and they first started sharing the pull-out couch. There are three doors in Charlie's apartment besides the front door, and way back in season 1, we saw that one of them was a bathroom. (Another is a closet, as Mac figured out when he briefly moved in with the duo in "Mac and Dennis Break Up" and cleaned the place.) They usually keep the doors closed and blocked with furniture, but it looks like Frank decided to look and found that their apartment has had a bathroom this whole time. That's a pretty big reveal for poor Frank, who has been peeing in cans and using a shared bathroom with no door down the hall for any other potty business. 

Why did Charlie keep the bathroom a secret? He tells Frank that it's a "bad toilet" but given what they've been living with, that's a pretty poor excuse. Maybe he was trying to keep Frank reliant on him to block the shared toilet while he poops? It wouldn't be out of character for Charlie, but having a bathroom in the apartment could be a big shift in their dynamic. After all, no one's going to poop the bed if there's a toilet just a few feet away.

The D.E.N.N.I.S. System

The presentation paper on an easel has become a running gag in "It's Always Sunny," much like the ancient video camera that the gang reuses over and over. However, one of its most important moments was when Dennis explained his "foolproof" system for seducing women: the D.E.N.N.I.S. System. The system was proven to not be totally "foolproof," in large part because of the gang, but it will be interesting to see why they're returning to it. Are we getting an updated version? Is Dennis trying to teach the lads the art of love again? Or is it potentially something more sinister? We'll have to wait and see!

The McPoyles are back, baby!

There are lots of zany people who circle the gang, but few are as fun as the McPoyles, a massive clan of inbred weirdos who have sworn vengeance against the gang for a variety of reasons. The gang and the McPoyles have been beefing since the first season, when Charlie foiled a plan to sue the local school district on made-up molestation charges, although tons of spats have happened since. Brother Liam (Jimmi Simpson) lost an eye at his wedding because Bill Ponderosa spiked the milk after Frank, his Narcotics Anonymous sponsor, let him do drugs, and another cousin was shot by Frank during tryouts for the Philadelphia Eagles, ruining his chances of making the team despite showing promise.

Liam and his twin/lover Ryan (Nate Mooney) have tried to make a living in some strange ways, and now it looks like they're working at a bowling alley. They previously owned a video store, so maybe they bought the place? Either way, it's just great to see the McPoyles!

Charlie is going America again

The gang are going for some seriously deep cuts this season, as Charlie's outfit from the season 2 episode "Charlie Goes America All Over Everybody's A**" is back, and he's ready to deliver some rock, flag, and eagle. We see him in what looks kind of like a school hallway, and later he and Frank are wrestling on a rug in what looks like a school gymnasium, so I'm expecting some kind of debate? I'm not sure how they got other people involved in their shenanigans, but we're going to see everyone's favorite patriotic clown try to be as American as he can be. Will the Birds of War show up? I sure hope so.

We also see Charlie in his limo driver outfit, chauffeuring the "Breaking Bad" guys (though they use different names and don't appear to be playing themselves.) He tries to explain the smell in the backseat, saying he vomited back there, which means it's the same limo from "Frank's Pretty Woman." Let's hope they steam-cleaned those seats.

Are they going to finally get that game of catch?

There wasn't a ton of Mac in the trailer, but we do see him in a graveyard with a baseball mitt, standing next to his hero/lifetime crush Chase Utley. Dream sequences and fantasies are fairly common in the series, so this could be anything, but maybe Mac's dad died and Chase Utley somehow ends up at the funeral? Or it's Utley's funeral and Mac goes to pay tribute and meets him as a ghost? Whatever it is, I really, genuinely hope they get to play that game of catch that Mac has been gunning for since season 2.

The greatest dance teacher to have ever waved

In one very brief sequence, we get to see one of those blow-up wavy dancer guys. One of them famously taught Dee (Kaitlin Olson) how to dance in "The Gang Buys a Boat," because he's got some pretty sweet moves. This is more of a silly little Easter egg than a cameo or throwback, but hey, it's a fun one! I wonder if he's dancing to P. Diddy boat music...

Season 16 of "It's Always Sunny in Philadelphia" will premiere on FXX on June 7, 2023, and the next day on Hulu.