It’s Always Sunny in Philadelphia has achieved what most shows can only dream about. Not only has the series made it to ten seasons (with another two on the way), it continues to be one of the funniest shows on TV. A decade after we first me the gang, they’re still as repulsive, lovable, clever, and idiotic as ever. Co-writers and co-producers Charlie Day, Glenn Howerton, and Rob McElhenney continue to take risks, delivering hilarious scripts and excellent performances, and Kaitlin Olson continues to claim the title of “most fearless comedic actress on TV”. Tonight's episode sees the gang on a televised game show a la Family Feud where they have to put on their game faces and collaborate to take home the win - the results are, of course, hideous.

I recently sat down with co-star and series creator Rob McElhenney for an exclusive interview. We talked about It's Always Sunny's longevity, why he likes writing for Dennis, his favorite episodes to shoot, making sure the series is constantly changing, and more.

This is a really strong season, and it's your tenth one. What do you think it is about the series that lends itself to that kind of longevity?

ROB McELHENNEY: The fact that we do only ten episodes a season is huge. Most networks do 22 or 24 episodes a year, so there's just a burn-out factor that we don't have to be concerned with. We've done ten years, but we've only done 114 episodes - which is still a lot, but most network shows at this point would be at 240 episodes. So that's a significant difference. Also, because we write the show and also act in the show we just can't take any episodes off. I think that just happens. I think that's the natural evolution to a lot of TV shows, because they're really difficult schedules and the writers eventually just start to get a little more relaxed in some of the story-breaking or some of the execution of the scripts. We recognize that we can't ever do that because otherwise who's going to go out there and say the words.

Do you like to write for your own character? Do you have a favorite character to write for?

McELHENNEY: I think Dennis is probably my favorite character to write for,  just because I think he's the easiest character to write for. He's a sociopath, so we just clicked in and know what's funny about that. And he's not just a dumb guy. Where with our characters it gets a little bit - we kind of fall back on Charlie's illiterate or Mac's just a bozo, with Dennis it challenges us to dig a little deeper.

Dee is such a special character on TV.

McELHENNEY: Yeah.

There's no other female character like her on TV and what Kaitlyn does with what you guys give her is incredible.

McELHENNEY: Yeah, that's really a testament to her. I think we created a really good character, but we did that in conjunction with Katie. Certainly at the beginning we weren't 100% sure we knew what was funniest about her, and then it was just a really great fusion of her sensibilities and our sensibilities to create Sweet Dee. To me she's the funniest woman on television.

Is there a particular episode that people really like to talk to you about?

McELHENNEY: Yes. Talking to me specifically, people like to bring up fat Mac quite a bit, so I'll talk about that season quite a lot. I'd say the episodes I hear most about - there's two episodes that I hear the most about from fans - "The Nightman Commeth" and the Chardee MacDennis episode, which I don't know, I always thought it was funny and fine. It was kind of miserable to shoot, but fans really seem to love it.

Why was it miserable to shoot?

McELHENNEY: Because we were screaming at each other for the entire thing and we didn't really have relief, so it was just scene after scene after scene around a table in the bar screaming at each other. We all lost our voices. I think it turned out OK, and I really like that episodes, but fans seem to really love it.

Is there an episode that you remember being very fun to shoot?

McELHENNEY: Yes. There's quite a few that are really fun to shoot. To me, the most fun scenes are when it's just a few characters in the bar or in Charlie's apartment or in Mac and Dennis's apartment, just kind of having very simple conversations. they're not super high concept, there's not a lot of yelling. One scene in particular I remember being very fun - I don't even remember the episode - it was just trying to get Charlie on Match.com and we're giving him an interview of what his interests are and taking a picture for his profile pic [laughs], I just remember it being a lot of fun because it was just me and Glenn sitting next to each other across from Charlie and just for 20 minutes just making each other laugh.

Milk steak.

McELHENNEY: Yeah, that's milk steak [laughs].

Classic. Going into your eleventh season and how you're approaching it, eleven seasons is a long time, and it's not so many episodes, like you said, but that's a lot of years for the audience to be with you guys. Are you still trying to change it up every season?

McELHENNEY: We try to change it up every episode. We want it to feel a little different. That's really the challenge that we face and something that I'm really proud of, which is that we continually try to stay true to the tone of the show and stay true to the characters so that you feel like you're watching an episode of Sunny, but that you're still continually surprised. That's difficult, because you can't sell out a character for a joke like a lot of shows do. You have to figure out ways in which you can challenge yourself and challenge the audience, and sometimes the audience doesn't respond. Sometimes they hate an episode. We've had certain episodes that people have just hated en masse because we tried something, we took a big swing, and they thought it just didn't work. From my perspective, I think that's what makes the show compelling, because we're willing to take those big swings and even though it may have failed in people's eyes, in the aggregate that's what makes it a success.

When you talk about risky episodes the first one that comes to mind for me is The Gang Broke Dee, that's a ballsy gamble.

McELHENNEY: Yep. And this season we have "Charlie Work", where half the episode is one shot. It starts like 8 or 9 minutes into the episode, and then for 11 or 12 minutes it's just one continuous shot. That was something that was really difficult for us, but it was something we wanted to try and it was fun. And it helps us stay focused and interested, to just keep chaging things and trying new things.

When you're the writers, actors, producers of a show like this, how all consuming can that be? Is it hard to sort of leave it in the office?

McELHENNEY: It's definitely not hard for me to leave it when I leave that office at night, when we leave the writer's room, I don't think about sunny until the next day. That's something that I worked on doing so that I wasn't just taking it back home with me, probably like season 4 or season 5, so I've had some practice with that. But once I'm there, it's pretty all consuming. Especially when you're in production. When you're shooting, you know - we used to do 12-13 hour days, but now we do 9-10 hour days and it can be intense, but as soon as I get in my car and I leave, I don't think about it again.

That's a great skill. I need to work on that.

McELHENNEY: It's really hard, especially as a writer. As an actor it's easy, because you're not...acting, but as a writer you can always be running through things in your head. I just have to actively turn it off.

So there are a lot of great episodes this year, what's the one you're most excited for people to watch?

McELHENNEY: There's an episode where we go onto a family feud type show called Family Fight and it was something that I wanted to do for the past t3 or 4 seasons and it just never came together, and this year we finally got it to come together. Keegan Michael Key play's the host of the show. He's just so brilliant. That's an episode I'm proud of. I think it's really funny.

It’s Always Sunny in Philadelphia airs Wednesdays at 10pm on FXX.