It's Always Sunny In Philadelphia Was Flying Blind For The Show's First Four Seasons

"It's Always Sunny in Philadelphia" may be the longest-running live-action sitcom, but the sun did not always shine bright for its cast and crew. During the first few seasons, there was an air of uncertainty surrounding the show's future. According to the faces behind the bar-owning gang, that feeling was amplified by the lack of awareness of the show's popularity. Shockingly enough, they only discovered that people were enjoying "It's Always Sunny" while on the heels of a fifth season.

Before the arrival of social media, it was nearly impossible for series creator Rob McElhenney and the rest of the cast to gauge how much the audience was invested in their unconventional sitcom. While the series continued to push the comedic limits of Paddy's Pub and its patrons, they did so under the assumption that it could all end at any moment. And, for the most part, they were content with that preconceived notion.

McElhenney detailed to Entertainment Weekly what the thought process was during the first few years of "It's Always Sunny in Philadelphia:"

"Probably for the first four years we were like, 'Oh, that was fun, but that's it. No one's watching, so we will just move on with it.' But we always thought we had something good, it was just a matter of getting people to watch it."

By the time the fifth season rolled around, the cast knew "It's Always Sunny in Philadelphia" was servicing an audience that closely watched the series. Furthermore, McElhenney and Kaitlin Olson detailed how difficult it was to know their show was popular, revealing that were even people coming to them trying to claim they were fans from the start:

McElhenney: "Season 5 was when we realized, 'Oh, there's an audience.”

Olson: "People came out of the woodwork, and everyone's thing was that they wanted to claim that they had been watching from the beginning."

McElhenney: "So there was no barometer, like you just really didn't know. It was only Nielsen ratings, which everyone kind of recognizes is bulls***. Now you can go on your phone and see exactly how people feel, or at least the vociferous 10 percent — we didn't even have that. And walking around L.A., no one seems to care anyway, because there are so many other shows and movies."

McElhenney does in fact pinpoint the exact moment they realized "It's Always Sunny" had a healthy and growing fanbase, referencing one specific event in the show's trajectory that changed their perspective forever. Hot off what was likely their best season finale yet, the cast had a firsthand look at just how many fans loved their wacky, darkly comedic series. Enter: "The Nightman Cometh."

In the finale of the fourth season, "It's Always Sunny in Philadelphia" decided to move away from its usual antics and delve deeper into the insane mindset of Charlie Kelly (Charlie Day) with his semi-autobiographical theater production "The Nightman Cometh." The episode featured Charlie employing his co-workers as fictional characters in his demented yet profoundly hilarious stage play in a ploy to win over the Waitress' heart. Not only was the episode a hit, but it also convinced the cast and crew to take the musical to real theaters across the nation. 

McElhenney revealed to Entertainment Weekly that after doing the live version of "The Nightman Cometh," "you got a good sense of how popular the show as." His co-showrunner Glenn Howerton (Dennis Reynolds) spoke to the Boston Phoenix about the impactful experience, revealing that it was a wake-up moment for how excited fans were to see them:

"It's a whole different experience, since we rarely get first-hand interaction. We knew the show had grown, and the interest was there, but none of us could have been prepared for the Troubadour [where the cast test-drove the musical]. You would have thought we were the Stones — people were singing every song along with us."

It's no surprise the catchy play translated well onto the real stage. Despite the ridiculous nature of "The Nightman Cometh," the show doubles down on the insane antics of its protagonists without feeling half-assed in its spontaneous musical endeavor. The fact it took four seasons for the "It's Always Sunny" crew to notice how popular the show was is shocking, but "The Nightman Cometh" being the sign of success for them speaks volumes about what they accomplished on the genre-defying series.