Spoiler alert! This article contains details of tonight’s season finale of FXX’s It’s Always Sunny In Philadelphia. Watch enough of It’s Always Sunny in Philadelphia and you’ll see the the Paddy’s gang dance their asses off. Maybe during the high school reunion episode of Season 7, when Mac (Rob McElhenney), Dennis (Glenn Howerton), Charlie (Charlie Day), Dee (Kaitlin Olson) and tag-along Frank (Danny DeVito) used dance as revenge on some snooty classmates. Or Season 4’s classic “The Nightman Cometh,” when Charlie wrote a musical to woo The Waitress (didn’t work). Or maybe Season 3’s dance contest episode, the one titled “The Gang Dances Their Asses Off.”

So McElhenney’s pas de deux (with a heretofore unknown female character, played by professional ballerina Kylie Shea) that closed tonight’s Season 13 finale didn’t seem terribly surprising – at least for, say, the first minute, maybe two. Five minutes in, though, and the wordless ballet, in which Mac expressed the true sexuality that has been obvious to his friends for years, took Sunny somewhere it hadn’t been, or at least hadn’t landed for more than a few seconds. Tonight, after years of increasing surrealism, outlandishness and meta humor, Sunny got serious.

Related Story 'It's Always Sunny In Philadelphia' Renewed For Record-Breaking Season 15 By FX

Day Patrick McElhenney/FXX

Actually, we shouldn’t be so surprised. Truth is, something even odder than a moment of emotion has been going on this fall on FXX: It’s Always Sunny In Philadelphia, one season shy of 14, has been turning out fresh, risky and genuinely funny episodes at a point long past most sitcoms hit the imploding dwarf star stage. Off the top of my head I can think of four Season 13 episodes – there might be more, but “The Gang Solves The Bathroom Problem,” “The Gang Does a Clip Show,” “Charlie’s Home Alone” and “Mac Finds His Pride” stand out for me – that could sit alongside the series’ all-time bests.

Olson, McElhenney, DeVito, Day, Howerton Patrick McElhenney/FXX

Here, McElhenney talks to Deadline about the personal inspiration behind tonight’s finale, about keeping a show sharp for 13 seasons, and about the worse-than-we-knew threat to Sunny posed when original cast member Glenn Howerton landed his NBC sitcom A.P. Bio. And we talk about McElhenney’s body.

This interview has been edited and condensed, but remains a pretty deep dive into Sunny history and lore. Skip over the references you don’t get – or better yet, check out It’s Always Sunny In Philadelphia on FXX or Amazon Prime. You have a 13-season binge just waiting for a dance.

Deadline: I think it’s fair to say this season’s finale was unlike anything we’ve seen on Sunny before.

Rob McElhenney: Very rarely do we have any kind of a real emotional resonance. We’ve been working on this show for 14 years and we want to just try different things, see what works and what doesn’t work. We like to stretch and do things that are a little bit scary.

Deadline: I can think of a couple moments where Sunny showed emotion – the tear falling down Charlie’s cheek after the Waitress slept with Frank, the look on Mac’s face when Dee gave birth [McElhenney and Olson had just become parents in real life, and the baby in Dee’s arms is their son Axel]. But it’s a long jump from those little moments to this finale. Was there any nervousness about taking fans where they weren’t used to going?

McElhenney: We stopped very early on trying to predict what people will respond to from us. We’ll be in the writers room and say, This episode is going to crush, or this particular joke or that particular moment, or this is something they’re going to talk about and want to see more of. Then it airs and you never hear from it again.

Then there are these other things that we just write not really even thinking too much about, and for whatever reason they resonate comedically or emotionally and you don’t even realize it until you see it on social media or you’re talking to people in public or we do a live show and you see how they’ve responded. We have absolutely no idea how to predict those things.

Deadline: Examples?

McElhenney: One big example specifically for my character was in the Night Man episode, Season Four. And I had nothing to do with this. Glenn and Charlie wrote a scene in which I was talking about how I’m going to cross the stage [during the gang’s musical The Nightman Cometh], and I said, I think I’ll do a little karate as I cross the stage – because I feel like Mac is somewhat of a ninja, and I had been training with a sensei on the side.

We shot it and didn’t really think that much of it again.

Later that year, we did a live performance of The Night Man Cometh here in LA and then we wound up doing it on a tour across the country. Every time I said “I’m going to do some karate across the stage” people went bizarrely nuts. I would come backstage and be, like, Did you guys hear that? What were they were cheering for? Glenn and Charlie were, like, maybe they think it’s funny.

So that became a character trait for Mac, literally something that we had just put in as an afterthought. When three thousand people are cheering for something in six major cities across the country, you’re like, oh, wow, maybe that really is resonating.

Deadline: At what point over the past 13 seasons did you realize your audience would go with you just about anywhere? And have there been times they refused?

McElhenney: We’ve had episodes that had almost a resounding negative response, where the vast majority of fans would say “swing and a miss.”

Deadline: “The Gang Cracks The Liberty Bell” (in which the gang tells a Revolutionary War-era tale) divides people. I think it’s one your best.

McElhenney: There was an episode in Season 6 about Frank’s brother, and it went back in time and tracked Frank’s relationship with his brother. That one got a resounding rejection. At least it did at the time. Charlie and Glenn and I, when we talk about that season, that to us is one of our funniest episodes. Some people say they’ve gone back and watched it a second time years later and appreciate it so much more.

McElhenney, Kylie Shea Patrick McElhenney/FXX

Deadline: So let’s talk about the dance at the end of tonight’s episode. The gang has always danced – from the dance marathon to Night Man to the high school reunion – but this was different. You were really dancing, ballet dancing. What made you think you could pull it off?

McElhenney: Well, the impetus was twofold. I wanted to do something with my character in regards to his sexuality, something that wasn’t just played for jokes but that would resonate emotionally, and I wasn’t 100 percent sure what that would be. We didn’t want it to seem pandering or off-tone or off-brand or just un-Sunny. So, how do we find a way in which it feels like you’re still watching the same show and yet we’re addressing something that is so important to our culture right now?

Now, couple that with the fact that I’ve always found myself to be a terrible dancer, and everybody says that I’m a terrible dancer including my wife and all of my friends. So thinking about wanting to do different things – and things that scare me and things that I’m terrible at – I thought wouldn’t it be fun to learn something new, use the show as an opportunity to grow and to learn something new? And that’s what we came up with.

Deadline: Mac’s being gay is a subject that means a lot to you, yes? Your mother is gay. How do personal experiences filter into your storytelling?

McElhenney: I was partly raised by two women, and I have two brothers who are gay, so I have always been part of the gay community. It’s just always been a part of my life. Mac’s sexuality wasn’t obvious to us in the beginning. Slowly but surely we realized we had an interesting opportunity. Mac was showing a lot of signs of being a closeted homosexual, and it could be interesting to have him come out. That’s something we wanted to address this year. And, yes, it was something that was important to me.

Gregory Scott Cummins Patrick McElhenney/FXX

Deadline: He came out last season to the gang, but in this season’s finale he comes out to his dad. But we didn’t get the expected I Love You Son moment. Quite the opposite. Given your personal history, was it difficult to see that potential bonding moment just vanish?

McElhenney: It would have felt inauthentic otherwise. Ultimately that’s why fans will come along with us for the vast majority of what we do – because anything we do has to feel authentic to the show. Even if we play with tone from time to time, and certainly content, certainly comedic structure, it all has to feel authentic to the show. It would have felt inauthentic to have Mac’s father have some sort of revolution emotionally and then to have Mac experience some kind of catharsis through that.

But we also wanted to make sure the episode didn’t end on a down beat, that it wasn’t sad. So what we realized in breaking the story down was that Frank really is the gang’s surrogate father, for better or worse. He is a terrible, terrible parent and he is a terrible father and he is a terrible, terrible role model, and ultimately a terrible person. And we have him throughout the episode not understanding Mac being gay, and having him reiterate over and over again “I don’t get it. I don’t judge you but I don’t get it. I don’t get it. I don’t get it.” All we wanted him to do in the end was to just wrap his mind around it and say to his ostensibly surrogate son, “I get it.” That’s it. We didn’t need him to say I love you or everything’s going to be okay. It’s just “oh, my God, I finally understand.”

Deadline: So, Rob, your body. You got incredibly buff for this season, and I read your tweet about how you achieved it, which might be the most honest thing a celebrity has ever said about getting in shape.

McElhenney: Back when I pitched [the idea] to Charlie and knew it was something I wanted to do for the season, I wanted to make it abundantly clear that there is nothing inherently funny about somebody getting legitimately ripped. Ripped people aren’t inherently funny unless the joke is about how they worked so long and so hard to look a very specific way, literally changing their entire lifestyle, only to find that no one around them cares. I thought that would be really, really funny.

I also thought it would be funny if, in a meta sense, an actor worked really hard in the same way that the character did to look a certain way, and then the television show he’s working on only lets him take his shirt off twice, basically rendering all of that work and the inability to enjoy one’s life almost completely useless, save for what amounts to about four minutes of content over the course of a year.

I just got to a point where it seems like every time you go to the movies or turn on a television show now, a man takes his shirt off and he’s inexplicably ripped. I don’t mean Hemsworth because he’s playing a Greek god, or Superman. I’m talking about the pizza delivery guy or the insurance salesman, and it’s because actors now read in the script that they have a sex scene and they have five months to prepare and they just get inexplicably jacked to the point where it just has to be your profession to look like that. I was getting sick of watching that, and I thought it would be funny to address that in a way that was true, which is that you have to devote everything to it, and you have to have the money, the resources, the time, and the ability to actually pull it off.

Deadline: Like Ross on Friends, the science nerd who kept getting in better shape with each season.

McElhenney: You find yourself watching shows in which people who are well into their 30s and 40s start to get better looking and you realize it’s because in real life they have more money, they have a personal trainer, they have the studio paying for the chef. If your face is plastered everywhere, you start to not be so happy with your teeth, or how pale your skin is. So you get a spray tan once a week. It’s so completely the opposite of what real life is, which is that as you grow older you do not look better.

Essentially, our characters on Sunny are alcoholics and treat themselves horribly and eat horribly. They would not look good. They would not look like Hollywood actors unless they devoted their entire lives to it, which I thought would be funny – for one season.

Deadline: After the Mac-gets-fat Season 7, you lost the weight pretty quickly, which regardless of money or studio backing, shows that your body responds pretty well to whatever it is you do to it. There’s some genetic stuff going on there too.

McElhenney: Sure, that’s an aspect of it. I have a certain kind of metabolism that allows for a certain kind of body type, and that made certain things easier and certain things harder.

Deadline: This is a silly conversation to be having on a phone, but I have to ask, what do you look like right now?

McElhenney: I am a normal person, although I’m doing a new show in a few months and I realized I should probably put on a few pounds, so I’m basically just drinking alcohol again and living normally.

Deadline: Getting jacked also played into the gay storyline, didn’t it, with Mac wanting the kind of muscle body he might see on a gay pride float. And you had a better haircut this season.

McElhenney: Thank you. And yes, we were just playing into the stereotypes that Mac would have about gay culture. That’s what I think is ultimately funny about him. What I’ve seen so many times with a gay character is that the joke is that he or she is gay. Oh, isn’t it funny that he or she is gay or bisexual or transgender? Obviously we wanted to distance ourselves from that. We’ve always wanted to figure out what was funny about this character being gay. Well, he is a hardcore Christian conservative and he is intensely homophobic. Now that’s something you can write to. That’s something where you can find the humor. Because clearly everybody around him – except him – knew that Mac was a gay man, and yet for so long he would not admit it. That gave us some runway for comedy.

Then we thought, now that he has come out of the closet, let’s have him embrace every gay stereotype, because that’s what he believes it is to be a gay man. Ultimately, what’s funny about Mac is that the characters around him, all of his friends, they don’t give a shit at all. It’s not that they don’t like Mac because he’s gay. They don’t like Mac because he’s annoying. And that is what we always thought was ultimately really funny.

Deadline: When Sunny first started, I think people had a hard time making the distinction between politically incorrect characters and a politically incorrect show. While there’s always been a progressive underscore to Sunny, there must be some things you wish you’d handled differently over 13 seasons. And you probably know what I’m getting at here.

McElhenney: There are things that, as we grow as a culture and as people, we understand a little bit more about ourselves and about humanity, and a little bit more about what is and isn’t offensive to people, and what’s demeaning or humiliating or just mean-spirited. There are certain things in Sunny‘s past – we can’t go back and ameliorate – but we probably would have handled differently. The quest of the show was always to be satirical, not trying to be profane for the sake of being profane or offensive for the sake of being offensive. We’re just exploring American culture and the human condition and using all of the tools in our toolbox. Our intention has never been to be offensive or mean-spirited. We oftentimes try to make the characters mean-spirited, homophobic and racist, but the joke is always on them.

Flirting with that line is dangerous and oftentimes in retrospect you look at things and think, I didn’t realize at the time but calling somebody a tranny is demeaning. Knowing that now, we would have handled that differently. It doesn’t mean that we wouldn’t have used the transgender character of Carmen in the same context, because if you watch those episodes Carmen is actually a paragon of morality. She is someone who ultimately the gang decides their baby is better off with – she will raise the child correctly, and Dee and Mac and Charlie and Dennis and Frank won’t. So the joke is never, Isn’t it funny that this woman is transgender? The joke was always that our characters are such pieces of shit that they can’t even see that this woman in front of them is a much better human being than they will ever be.

McElhenney, Howerton, Olson, DeVito Byron Cohen/FXX

Deadline: Since we’re in a reflective mood, let’s talk about this season’s clip show. It started out like a traditional clip episode, and then got very weird, with fake clips and mis-remembered episodes. And Danny DeVito with very long legs, one of the show’s funniest visuals ever. At what point did you decide to do a clip show, and then at what point did you decide to subvert that very idea?

McElhenney: We’ve talked about doing a clip show for years, and what always came up was that it felt derivative. Or it felt lazy more than anything else. But I would always beg Glenn and Charlie to just watch some clip shows with me because I promise you it is an incredibly enjoyable experience. So this year I finally got Charlie to sit down with me and watch the Roseanne episode where they did clips, and the Seinfeld episode when they looked back on the series. What you realize is you’re watching these shows because you like spending time with these people, and you want to spend time reminiscing and thinking about past events and talking and joking and sort of reflecting. So why wouldn’t we do that with these characters we’ve played for 13 seasons?

But we’ve always tried to subvert the paradigm of the sitcom, so what would be our version of a clip show? Once we started talking about it like that, we realized a clip episode was something we could do.

Deadline: You had the Sunny characters mis-remembering themselves in the Seinfeld episode “The Contest.” Now, once you’ve taken the comedy to a place that bizarre, where can you go next? Does it ever enter your mind what you’ll do for Season 14?

McElhenney: No. Not even a little bit. I made a concerted effort very early on to not think about Sunny at all once the season is over, and then I wait until the very first day in the writers room to open that part of my brain back up and restart the conversation. I willfully keep it out of my head for the better part of a year.

Howerton Patrick McElhenney/FXX

Deadline: How big of a challenge was it this year to have Glenn Howerton splitting his time between Sunny and his other show, NBC’s A.P. Bio? I was expecting him to have much less of a presence on Sunny – he wasn’t gone nearly as much as I had expected.

McElhenney: That was our intention. Very early on we were pitching ideas on how we would do the season without him completely and it just didn’t work. We went back to Glenn and ultimately back to NBC and said we want to figure out a way to get you involved because we don’t think the show works without you. But his schedule being what it was – and NBC not really letting him do all 13 [Sunny episodes] – we wanted to find a way in which it felt like he was there all season. I’m glad to hear you say it felt like he was there more than he was, because that was very much intentional. The show just doesn’t work without him. We thought we could make it work and we just can’t. If you take one element out of the equation, everything falls apart.

Deadline: The season is over so you’re not thinking about Sunny now. What’s the next period of your life going to be like?

McElhenney: I’m working on another show right now that will be premiering sometime next year. It is for a new streaming service and the platform is also going to launch sometime next year. That’s all I’m really allowed to say about it. I think it’s going to be a pretty big deal, a pretty big endeavor and I’m happy to be a part of it.

Deadline: But don’t you have a movie coming? [Editor’s Note: McElhenney previously was attached to direct a big-screen adaptation of Minecraft.]

McElhenney: No. That’s no longer happening. The movie business is brutal. Everything just keeps getting pushed and pushed and pushed and you’re just supposed to sit around and wait for the opportunity to go devote two-and-a-half years of your life to something that ultimately will seclude you from anything else in your life. I wound up taking almost a year off from Sunny and eventually I said I have to go back to my show. It was the best decision I could have ever made.

Olson Byron Cohen/FXX

Deadline: Well, I agree. So let’s end with a softball: Kaitlin Olson, the best physical comedian on TV today?

McElhenney: Can you please print this in bold italics with exclamation points? Sold!!!!